MEETING OF THE ADVISORY 

COMMITTEE ON IMMUNIZATION 

PRACTICES (ACIP)

APRIL 19, 2023

MEETING SUMMARY

CONTENTS

WEDNESDAY: APRIL 19, 2023.................................................................................................................... 2

WELCOME AND INTRODUCTIONS ...................................................................................... 2

Call to Order/Roll Call ......................................................................................................... 2

Announcements.................................................................................................................. 2

COVID-19 VACCINES............................................................................................................ 4

Session Introduction ........................................................................................................... 4

COVID-19 Vaccine Program Updates................................................................................. 4

mRNA COVID-19 Bivalent Booster Vaccine Safety Update ................................................ 7

v-safesm After Vaccination Health Checker.........................................................................12

COVID-19 Vaccine Effectiveness Updates.........................................................................14

Updates to COVID-19 Vaccine Policy: Considerations for Future Planning........................19

Updates to Interim Clinical Considerations for Use of COVID-19 Vaccines........................23

PUBLIC COMMENT ..............................................................................................................29

Overview............................................................................................................................29

Public Comments...............................................................................................................29

CERTIFICATION.........................................................................................................................................33

ACIP MEMBERSHIP ROSTER ..................................................................................................................34

ACRONYMS USED IN THIS DOCUMENT................................................................................................. 42
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WEDNESDAY: APRIL 19, 2023

WELCOME AND INTRODUCTIONS

Call to Order/Roll Call

Dr. Grace Lee (ACIP Chair) called to order and presided over the April 19, 2023 Advisory 

Committee on Immunization Practices (ACIP) meeting. Dr. Lee conducted a roll call, which 

established that a quorum was present. A list of Members, Ex Officios, and Liaison 

Representatives is included in the appendixes at the end of this summary document. No

conflicts of interest (COIs) were identified. The following potential COI was identified:

 Dr. Camile Kotton is involved in a clinical trial for Takeda for an investigational antiviral that 

does not involve any work with vaccines.

Announcements

Dr. Melinda Wharton (ACIP Executive Secretary, CDC) noted that copies of the slides for the 

meeting were available on the ACIP website and were made available through a ShareLinkTM 

file for voting ACIP Voting, Ex Officios, and Liaisons Members. The ACIP is, at its heart, a public 

body. Engagement with the public and transparency in all of its processes are vital to the 

committee’s work. She indicated that there would be 1 oral public comment session during this 

meeting, which was scheduled for 1:30 PM Eastern Time (ET). To create a fair and more 

efficient process, individuals interested in making an oral comment were asked to submit a 

request online in advance of the meeting. Priority is given to these advance requests. If more 

people make requests than can be accommodated, a blind lottery is conducted to determine 

who the speakers will be. Speakers selected in the lottery for this meeting were notified in 

advance of the meeting. Members of the public also may submit written comments via 

https://www.regulations.gov using Docket Number ID CDC-2023-0028. Information on the 

written public comment process, including information on how to make a comment, can be 

found on the ACIP website.

As noted in the ACIP Policies and Procedures manual, ACIP members agree to forgo 

participation in certain activities related to vaccines during their tenure on the committee. For 

certain other interests that potentially enhance a member’s expertise while serving on the 

committee, CDC may issue limited COI waivers. Members who conduct vaccine clinical trials or 

serve on data safety monitoring boards (DSMBs) may present to the committee on matters 

related to those vaccines, but those members are prohibited from participating in committee 

votes on issues related to those vaccines. Regarding other vaccines of the concerned company, 

a member may participate in discussions with the provision that he/she abstains on all votes 

related to that company. ACIP members state any COIs at the beginning of each meeting.

Dr. Wharton reported that Since the COVID-19 vaccination program began in the United States

(US) in December, 2020, more than 670 million doses of COVID-19 vaccines have been

administered to 270 million people. A lot has happened since the original authorizations of 

COVID-19 vaccines. There have been multiple changes to recommendations for vaccine use as 

additional vaccines became available and vaccines were authorized for additional age groups.

During the February 2023 ACIP meeting, there was discussion of future directions for the

COVID-19 vaccination program. This proposal included moving toward a single dose of an
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updated vaccine for most people, and additional doses needed only for young children who may 

not yet have been exposed to COVID, older adults, and immunocompromised people. With the 

previous day’s regulatory action by the Food and Drug Administration (FDA), a large step was 

taken in this direction. She invited colleagues from the FDA to provide an update on that action.

Peter Marks M., PhD (CBER/FDA) indicated that FDA’s ultimate objective is to improve public

health by facilitating better updated COVID-19 vaccine coverage and those eligible for 

vaccination. The previous day’s action was an initial effort, based on the totality of evidence

available, to simplify the vaccination regimen for most individuals and authorize the current 

bivalent vaccines to be used for all doses administered to individuals 6 months of age and older, 

including an additional dose or doses for certain populations. Most individuals, depending on 

age previously vaccinated with an original or monovalent COVID-19 vaccine, who have not

yet received the dose of a bivalent vaccine, may receive a single dose of a bivalent vaccine.

Most unvaccinated individuals may receive a single dose of a bivalent vaccine rather than

multiple doses of the original monovalent mRNA vaccines in order to be considered protected.

Most individuals who have already received a single dose of the bivalent vaccine are not 

currently eligible for another dose with some exceptions. The FDA intends to make decisions

about future vaccination for all of the various populations after receiving recommendations on 

the strain composition at an FDA Vaccines and Related Biological Products Advisory Committee

(VRBPAC) meeting to be held in June 2023, at which time strain selection will be discussed

for the coming year or season. As noted, individuals 65 years of age and older who have 

received a single dose of a bivalent vaccine may receive one additional dose of vaccine at least 

4 months following their initial bivalent dose. Most individuals with certain kinds of 

immunocompromise who have received a bivalent COVID-19 vaccine may receive a single 

additional dose of a bivalent COVID-19 vaccine at least 2 months following a dose of that

vaccine. Additional doses may be administered at the discretion of and intervals determined by 

their healthcare provider (HCP). The one exception is for immunocompromised individuals 6 

months through 4 years of age for whom the eligibility for additional doses will depend upon the 

vaccine previously given to the individual. Children 6 months through 5 years of age who are

unvaccinated may receive a 2-dose series of the Moderna bivalent vaccine. Children 6 months 

through 4 years of age may receive a 3-dose series of the Pfizer-BioNTech bivalent vaccine.

Children 5 years of age may receive either 2 doses of the Moderna bivalent vaccine or a single 

dose of the Pfizer-BioNTech bivalent vaccine. Children 6 months through 5 years of age who

have received 1, 2, or 3 doses of a monovalent COVID-19 vaccine may receive a bivalent

vaccine, which is essentially to complete that initial vaccination series. FDA realizes that this 

updated regimen is still somewhat more complicated than desirable but views it as an interim 

step moving into the next cycle of strain selection, which is coming up in late Spring to early 

Summer. FDA will further consolidate and simplify the regimen as labeling is further updated for 

these vaccines. Ultimately, the goal is to have the regimen simple enough for patients to easily 

understand and providers to easily administer. For now, the key message is that for older

children and adults up to age 65, a single bivalent vaccine is appropriate for prevention of 

COVID-19 under the current Emergency Use Authorization (EUA). In terms of those who have 

received non-mRNA vaccines, FDA will be discussing with manufacturers how to further update 

those vaccines so that there will be options available moving forward. The previous day’s action 

does not affect those vaccines at this time.

Dr. Grace Lee (ACIP Chair) thanked FDA colleagues for their continued attention to addressing 

the COVID-19 pandemic, recognized that this is an evolution of recommendations or 

authorizations over time, and expressed appreciation for FDA’s attempt to a more simplified 

future state.
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COVID-19 VACCINES

Session Introduction

Dr. Matthew F. Daley (ACIP WG Chair) introduced this session on behalf of the ACIP COVID19 Vaccines Work Group (WG). As they just heard from Dr. Marks, there were FDA

authorizations on April 18, 2023 that included updating the COVID-19 Vaccine EUA, including

the use of bivalent mRNA vaccines for all doses and indications administered to individuals 

ages 6 months and older and additional doses for certain specific populations.1

Since the February 2023 ACIP meeting, the COVID-19 Vaccines WG reviewed a number of 

data points around pediatric COVID-19 vaccination. They also reviewed the epidemiology of 

COVID-19, including among adults ≥65 years of age. The WG heard a number of vaccine

effectiveness (VE) updates. In addition, they reviewed preliminary results from pediatric costeffectiveness analyses and discussed additional doses in vulnerable populations. The February 

24, 2023 ACIP meeting included COVID-19 updates and discussions on vaccine safety, VE, 

and epidemiology and hospitalization data. In addition, there were presentations and 

discussions on a benefit-risk analysis, considerations for transition to a bivalent primary series, 

and future directions of COVID-19 vaccines, including updates to vaccine policy. 

The session on April 19 included vaccine safety updates, VE data updates, presentations on 

epidemiology and hospitalization data and a benefit-risk analysis, considerations for transition to 

bivalent primary series, and discussion on future directions of COVID-19 vaccines—including 

updates to vaccine policy. 

COVID-19 Vaccine Program Updates

Georgina Peacock, MD, MPH, FAAP (CDC/NCIRD) presented COVID-19 Vaccine Program 

updates. As a reminder, she reviewed the key objectives that were set forward at the beginning 

of the pandemic, which were to: 1) ensure safety and effectiveness; 2) reduce mortality, 

morbidity, and the incidence of COVID-19 disease; 3) help minimize disruption to society and 

the economy, including maintaining healthcare capacity; and 4) ensure equity in vaccine

allocation and distribution.

Moving into the next phase, it is important to keep these objectives in mind for the US COVID19 Vaccination Program. In terms of the reasons for changes in the program, the Public Health 

Emergency (PHE) will end on May 11, 2023. Regarding what will change, it is possible that 

there will be reduced submission of vaccine administration data from some jurisdictions on a 

national level. This is going to limit the completeness of the administration data that can be 

reported report on a national level. CDC has been working with jurisdictions to sign an extension 

of their COVID-19 Data Use Agreements (DUAs) that will extend CDC’s ability to get data from

most states until the end of 2023. It is expected that that a few jurisdictions may not submit 

those data based on state laws and other issues that are impacted by the end of the PHE. 

Nevertheless, CDC still will be getting the majority of administration data on COVID-19 

vaccines. Other things will not change. CDC will continue to work with public and private

partners to learn more about the short- and long-term health effects associated with COVID-19

in terms of who is affected and why and to implement vaccine recommendations to optimize

1 https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-changes-simplify-usebivalent-mrna-covid-19-vaccines 
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protection. FDA’s EUAs will remain in place for COVID-19 products, including vaccines, even 

beyond the PHE. All vaccines purchased by the US Government (USG) will continue to be 

distributed and available for free. CDC is committed to ensuring a strong immunization program 

going forward as changes continue to occur.

Commercialization of COVID-19 vaccines is expected to occur in early Fall 2023. 

Commercialization is the transition of vaccines previously purchased by the USG to established 

pathways of procurement, distribution, and payment for vaccinations by public and private 

payers.2 Considerations include what will be authorized by FDA and recommended by CDC, 

and the alignment with any strain changes due to potential variants. After commercialization, 

vaccines will remain free for most people through the Vaccines for Children Program (VFC), the 

Children’s Health Insurance Program (CHIP), most commercial insurance, and Medicare and 

Medicaid programs. 

A focus on vaccination equity has been a very important part of the COVID-19 Program. CDC 

has been working with national, state, tribal, and territorial health departments; healthcare; and 

community partners to ensure that all people have fair and just access to vaccination. This effort 

also has addressed many issues related to vaccine confidence. Given that access and 

confidence go hand-in-hand, there has been a major emphasis on these over the past couple of 

years. CDC uses a Social Vulnerability Index (SVI)3 to support areas that are at increased risk. 

The SVI allows health departments and others to look at vaccine coverage at the sub-county

and Census track levels to determine where there is social vulnerability in order to target efforts 

to increase vaccine coverage. Making sure that uninsured adults have continued access to

COVID-19 vaccines with as few financial barriers as possible is a top priority.

An important announcement was made by the HHS Secretary in the last few days that there will 

be an “HHS Bridge Access Program For COVID-19 Vaccines and Treatments” for uninsured 

adults.4 This program is being put in place to serve the 30 million uninsured adults in the US.

This supports the existing public sector vaccine safety net. Traditionally, CDC has worked with

state and local health department partners to make vaccines available through the 317 Program 

that provides vaccines and supportive infrastructure to vaccinate uninsured adults. Funding for 

this effort will be made available through this existing program. Funding also will be going to 

Federally Qualified Health Centers (FQHCs). In addition, there will be a funded partnership with 

pharmacy chains. This will allow another way for uninsured adults to be able to receive vaccines 

free of charge. A major development over the last couple years and throughout the pandemic is

that pharmacies have been a key partner in helping to increase access to COVID vaccine. 

Pharmacy partners administered COVID vaccine during the pandemic, which is an important 

model in terms of consideration of the domestic vaccine program. CDC is committed to thinking 

through and supporting pharmacy networks in terms of moving forward in this new phase of the 

COVID vaccine program. One of the ways to do this is through the Bridge Program for the 

uninsured.

2 https://aspr.hhs.gov/COVID-19/Pages/FAQ-Commercialization.aspx 3 https://www.atsdr.cdc.gov/placeandhealth/svi/at-a-glance_svi.html 4 https://www.hhs.gov/about/news/2023/04/18/fact-sheet-hhs-announces-hhs-bridge-access-program-covid-19-vaccines-treatmentsmaintain-access-covid-19-care-uninsured.html
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Another issue that has arisen that affects the COVID-19 Vaccine Program is the Public 

Readiness and Emergency Preparedness Act (PREP Act) for Medical Countermeasures against 

COVID-19.5 HHS recently announced an intention to amend the declaration under the PREP 

Act for Medical Countermeasures against COVID-19. By issuing this amendment, the HHS 

Secretary intends to extend immunity liability to pharmacists, pharmacy interns, and pharmacy 

technicians to administer COVID-19 and seasonal influenza vaccines through December 2024.

This amendment will allow for the ability of pharmacists to vaccinate children for routine 

vaccinations down to 3 years of age.

Another important development is the Inflation Reduction Act,6 which includes some key

provisions that eliminated cost-sharing for all ACIP-recommended vaccinations under Medicaid 

and Medicare Part D or equivalent plans. This started on January 1, 2023 and is continuing to 

be implemented. While not yet fully in place, it guarantees that nearly 50 million Medicare

beneficiaries and more than 80 million Medicaid beneficiaries will have access to all ACIPrecommended vaccinations for adults without any cost-sharing. This is a very important

development for the coverage of vaccines across the lifespan.

Despite these advances, a comprehensive Vaccines for Adults (VFA) Program is still needed 

that will fill in the gaps in places where no coverage is currently available. The proposed VFA 

would reduce the spread of vaccine-preventable diseases and pave the way for greater health 

equity. In CDC’s FY24 President’s Budget Request, there is a request for the proposed VFA

Program. This $1.2 billion request for FY24 equates to $12 billion over 10 years that would be 

utilized for vaccine purchase, program operations, provider administration, and provider fee

reimbursement. This would cover all ACIP-recommended vaccines for uninsured adults, which

equates to approximately 30 million people in the US. In addition to this, not included in the VFA 

proposal, is the important provision for the support of vaccine confidence and equity activities 

need to continue through the discretionary funding related to Section 317.

Discussion Points

Dr. Duchin (IDSA) expressed concern about cessation of reporting of vaccine administration 

data, given that it seems critical to ensuring equity in access and distribution. He requested 

information about how this gap would be addressed long-term and whether it is part of the new 

informatics initiative the CDC is working on. He applauded the movement forward in terms of 

the Adult Vaccination Program after so many years of advocacy by the National Vaccine 

Advisory Committee (NVAC) and others and asked what specifically would be provided to state

and local health departments that administer these vaccines and carry out many of the

relationships with community providers.

Dr. Peacock emphasized that there has not been complete cessation of reporting of

administration data. There will be some decreases after this PHE, most of which is related to 

state laws that prohibit sharing these data with the federal government. CDC is working with its 

state partners to determine whether there are ways to continue to receive vaccine 

administration data related to COVID and routine vaccinations. Putting an extension of the

DUAs into place for COVID and negotiation of routine vaccination DUAs should be helpful. For 

COVID vaccines, the CDC COVID-19 Vaccination Program Provider Agreement is still in place. 

At the peak, over 120,000 providers were providing COVID vaccine. The agreement includes a 

provision that providers need to report administration data of COVID vaccine. While it is 

5 https://www.hhs.gov/about/news/2023/04/14/factsheet-hhs-announces-amend-declaration-prep-act-medical-countermeasuresagainst-covid19.html 6 https://www.cms.gov/newsroom/fact-sheets/inflation-reduction-act-lowers-health-care-costs-millions-americans 
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probable that CDC will not have the full picture of what is occurring nationally, state health 

departments will still have these data within their Immunization Information Systems (IISs). It will 

still be necessary to consider ways to ensure equity moving forward. There will be challenges, 

but CDC has supported many partners who have been working with community-based 

organizations (CBOs) to examine access and confidence issues. This work is continuing to be 

funded and move forward. In relation to the Adult Program and support of state and local health 

departments, that work is critical. As a domestic program is implemented that serves people 

across the lifespan, the infrastructure that has been built to serve children over the last 30 years 

through the VFC Program serves as a basis for providing vaccines for adults through a VFA

Program. Built into that is an increase in the infrastructure, which is essentially the jurisdiction

awardee that CDC funds. That is an important part of the VFA proposal.

Dr. Sanchez requested clarification with regard to the amendment to the PREP Act in terms of 

children down to 3 years of age and how that applies to vaccine provided to children and

pregnant women. 

Dr. Peacock clarified that the PREP Act allowed for a number of vaccinators to vaccinate people 

all down to 3 years of age. Typically, there are state laws that differ by state that designate who

can be vaccinators. The PREP Act extended the ability to vaccinate to pharmacists, pharmacy 

techs, and pharmacy interns for COVID-19 vaccine, influenza vaccine, and routine childhood 

vaccination. This has been ongoing throughout the pandemic. The amendment to the PREP Act

allows certain provisions to continue. Certain provisions allow influenza and COVID vaccination

to continue down to 3 years of age, so there is coverage across the nation for that. That

provision was not extended for routine childhood immunization, which now revert back to state 

laws. She apologized for not having any details on pregnant women.

Dr. Daley expressed gratitude for the continuing advocacy for the VFA Program. Although death 

from COVID-19 is largely vaccine-preventable, it seems completely unfair that the ability to 

access that vaccine is related to whether someone has health insurance. 

Dr. Peacock stressed that the announcement of the Bridge Program represented an important

step forward toward ensuring administrative of a vaccination program that serves people across 

the lifespan.

mRNA COVID-19 Bivalent Booster Vaccine Safety Update

Tom T. Shimabukuro, MD, MPH, MBA (CDC/NCEZID) described current data on ischemic 

stroke following mRNA COVID-19 bivalent booster vaccination from the following systems:

 CDC’s Vaccine Safety Datalink (VSD) Rapid Cycle Analysis (RCA) signal assessment for 

ischemic stroke after Pfizer-BioNTech COVID-19 mRNA bivalent booster dose vaccination 

in the age group ≥65 years old

 Vaccine Adverse Event Reporting System (VAERS) data on ischemic stroke following 

mRNA COVID-19 bivalent booster dose vaccination

As a reminder, the VSD is CDC’s active, electronic health record (EHR)-based surveillance 

system that was established in 1990 as a collaborative project between CDC and 9 integrated 

healthcare organizations. These analyses included the 9 participating sites that have data on a 

total of about 12.5 million individuals.
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VSD RCA pre-specified outcomes were assessed during weekly sequential monitoring after

bivalent booster vaccination. The risk of pre-specified outcomes in 1 to 21 days following

vaccination were compared with bivalent vaccinated individuals who were 22 to 42 days out

following the bivalent dose. This is a vaccinated concurrent comparator method that assesses 

cases in vaccinated individuals in the risk window of 1 to 21 days compared to cases in

vaccinated individuals in the comparison interval at 22 to 42 days. All analyses were adjusted 

for age, sex, race and ethnicity, VSD site, calendar time (days), and seasonality (time). The

signaling threshold is a 1-sided p-value <0.01.

This table shows the pre-specified outcomes that were monitored in the COVID-19 Vaccine 

RCA and the settings in which they were monitored:

In the COVID-19 booster vaccination monitoring, the RCA detected a statistical signal for 

ischemic stroke after Pfizer-BioNTech bivalent booster vaccination in the age group 65 years 

and older. No other VSD RCA pre-specified surveillance outcomes have signaled in any age 

group for either of the mRNA COVID-19 bivalent boosters or when data for the 2 mRNA vaccine 

types were combined or pooled. VSD investigations of an RCA signal to assess whether it 

reflects a real effect of vaccination on an outcome include several steps, including the following:

 Data quality assessment for errors, anomalies, or missing or late-arriving data

 Analyses using different comparators than the primary concurrence (e.g., un-boosted,

unvaccinated, or “historical” comparators) to supplement the primary analyses

 Additional investigations to provide context, such as background rates

 Graphic displays of outcome incidents, day-by-day after vaccination, using temporal scan 

statistics to assess apparent clustering to examine the temporal clustering of outcome 

events in subgroups defined by demographics, site, or simultaneous exposure (e.g., 

influenza vaccine)

 Further analyses by site or subgroup conducted as appropriate if the signal is driven by a 

strong association in one subgroup or VSD site

 Chart review to confirm cases and collect additional data, such as date of symptom onset

 Consideration of epidemiologic studies to further investigate surveillance findings
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Moving now to the results of the VSD COVID-19 RCA analyses of ischemic stroke after PfizerBioNTech bivalent booster among people ≥65 years of age, substantially more Pfizer-BioNTech 

(643,372) booster vaccines were administered during the bivalent booster program compared to 

Moderna (355,767) between 8/28/22 and 4/8/23. There were substantially more doses 

administered early in the booster program, with the peak of COVID-19 bivalent booster with

Pfizer-BioNTech at about the same time as peak influenza vaccination in this age group.

This table reflects the VSD RCA ischemic stroke case definition, onset date, codes to detect 

prevalence, and exclusion criteria:

In terms of the bivalent RCA concurrent comparator analysis of ischemic strokes during a 1- to 

21-day risk interval versus a 22- to 24-day comparison interval, the primary analysis was the 

vaccinated concurrent comparator, shown for the most current weekly analysis with data 

through April 8, 2023. This analysis was broken down by age groups 18─64 years and 65+ 

years. While younger age groups were assessed, ischemic stroke is a very rare outcome and 

those data are not informative for this analysis. For the most recent sequential analysis by the 2 

age groups and by vaccine (Pfizer, Moderna) none of the findings met the signaling threshold,

which is a p-value of <0.01. In the nominal analysis, all the 95% confidence intervals included 

1.0, so it also was not statistically significant. As Dr. Shimabukuro recalled, the last time he 

showed these data, the nominal analysis for Pfizer vaccine among persons ≥65 years of age the

was statistically significant and the sequential analysis did not hit the signaling threshold.

In the weekly analyses ischemic stroke after Pfizer-BioNTech bivalent booster for persons age 

≥65 years from October 16, 2022 through April 8, 2023, the rate ratio was 1.26 with a 95% 

confidence interval of 0.99 to 1.60 as of April 2, 2023. A statistical signal for ischemic stroke

following the Pfizer-BioNTech bivalent booster in this age group was first detected in November

2022. This signal persisted through January 2023, but did not meet the signaling threshold for 

the last 10 weekly analyses. An important caveat is that in the VSD RCA, once there is a signal, 

there always is a signal. While the most recent 10 weekly analyses did not meet the statistical

threshold for a signal, there still was a signal for this outcome. However, CDC continues to 

follow these weekly analyses over time because they think it is informative to do so.
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In addition to the primary analysis, supplemental analyses also are performed. The 

supplemental RCA analyses assessing ischemic strokes in the 1- to 21-day risk interval 

comparing bivalent boosted to unboosted concurrent comparators can be thought of as a 

vaccinated versus unvaccinated comparison. A note for this particular analysis is that it is not 

truly a vaccinated versus unvaccinated: it is a bivalent boosted versus unboosted, but eligible 

for a booster. These individuals probably are more similar than true vaccinated versus

unvaccinated. In the supplemental analyses, the adjusted rate ratio was 1.01 (0.86─1.19) and 

was not statistically significant.

As mentioned earlier, much of the vaccination with the Pfizer-BioNTech bivalent booster was

occurring at the same time as peak influenza vaccination in the VSD in persons ≥65 years of 

age. A substantial number of the cases in the risk window also had simultaneous influenza 

vaccination. Most of the individuals ≥65 years of age who had simultaneous influenza 

vaccination received a high-dose or adjuvanted influenza vaccine, which might be expected 

because those vaccines are preferentially recommended. A stratified analysis was conducted to 

assess ischemic stroke incidence during the risk window compared to the comparison window 

among persons ≥65 years of age, with and without simultaneous influenza vaccination. For 

individuals who received the bivalent Pfizer-BioNTech booster and simultaneous high-dose or 

adjuvanted influenza vaccine, the adjusted rate ratio was elevated but not statistically significant

at 1.59 (0.99─2.61). The bivalent Pfizer-BioNTech bivalent booster without any same day

influenza vaccine had an adjusted rate ratio of 1.01 in February 2023 in the simultaneous group

and was statistically significantly elevated. It is now attenuated and is no longer statistically 

significant.

To summarize, the statistical signal persisted during the November to January timeframe. The 

rate ratio has slowly attenuated from 1.92 to 1.26 and has not met signaling criteria during the 

past 10 weekly analyses. Supplemental analyses using an unboosted concurrent comparator

showed a rate ratio of 1.01, which was not statistically significant. Analyses evaluating

simultaneous high-dose or adjuvanted influenza vaccine showed a rate ratio of 1.59, which also 

was not statistically significant. Separate analyses did not detect an elevated rate ratio for stroke 

after influenza vaccine alone. In previous presentations, data from some supplemental analyses 

suggested comparison interval rates were lower than expected. There can be several reasons

an elevated rate ratio might be seen. There may be more than expected cases in the risk 

window compared to the comparison window, less cases than expected in the comparison 

window compared to the risk window, or a combination of two. Data previously presented in 

February suggested that there was some evidence of a lower rate in the comparison interval 

than would be expected.

Moving on to VAERS. As a reminder, VAERS is the national spontaneous reporting or passive 

surveillance system that is co-managed by CDC and FDA. This system is good at rapidly 

detecting safety signals and rare adverse events (AEs). As a spontaneous reporting system, its 

main limitation is that causality cannot be assessed based on VAERS data alone. In general 

summary of US reports to VAERS following bivalent booster COVID-19 mRNA vaccination

among people ≥5 years as of April 2, 2023 (N=28,363), the distribution by age, sex, and serious 

status was similar regardless of manufacturer. For both Pfizer-BioNTech and Moderna 

vaccines, 93% of reports were non-serious. That is consistent with what has been observed with

other monovalent booster vaccinations.

In terms of reports to VAERS of ischemic stroke or transient ischemic attack (TIA) after bivalent

COVID-19 mRNA vaccination in people ≥18 years of age after bivalent vaccination as of April 2, 

2023, there were 252 preliminary reports of ischemic stroke or TIA. Of these, 34 are still under 
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review, 9 were excluded based on chart review, and 60 were non-ischemic strokes verified by 

chart review. That left a total of 149 verified reports of ischemic stroke or TIA comprised of 110 

ischemic strokes, 35 TIAs, and 4 ischemic stroke + TIA. There are 112 Pfizer BioNTech bivalent 

cases and 37 Moderna bivalent cases. The median age was 72 years, median time to onset 

was 13 days, 68 were in males and 81 were in females. All 149 verified reports had at least 1 

risk factor for ischemic stroke, with the most common being hypertension. Some of these cases

received simultaneous influenza vaccination. In those 18─64 years of age, 6 had simultaneous 

administration with standard dose influenza vaccine. Among those ≥65 years of age, 1 had 

high-dose, 3 had adjuvanted, 2 had standard dose, and 1 had an unknown type of influenza 

vaccine. This table shows VAERS reports and reporting rates of ischemic stroke and TIA in the 

3 weeks after bivalent vaccination people 18─39, 40─64, and ≥65 years of age:

This is limited to reports with onset within the 3 weeks, so the observed reports are the verified 

VAERS reports in these specific age and vaccine strata. The chart verified reports plus reports 

under review is essentially a sensitivity analysis in which the reports under review are assumed 

to be true reports. The easiest way to explain this, focusing on the bottom row, this is saying 

that within in a hypothetical cohort of individuals ≥65 years of age (9.6 million individuals) about 

3,500 stroke or TIA cases would be expected in a 3-week period. The background rates are 

based on the references at the bottom of the table. These are these observed versus expected

cases, which requires some assumptions. While this is not a perfect analysis, it does provide 

some perspective on what is being observed compared to what would be expected based on 

background. To provide some information on stroke in general from CDC statistics, about every 

40 seconds someone in the US has a stroke and about every 3.5 minutes somebody dies from 

a stroke. About 87% of strokes are ischemic strokes. In this analysis, no unusual or unexpected

reporting patterns were observed and no evidence of a safety concern was detected for 

ischemic stroke with either mRNA COVID-19 bivalent booster in VAERS monitoring.

In terms of COVID-19 mRNA bivalent booster vaccination safety data from other monitoring 

systems and programs,7 FDA monitoring in the Center for Medicare and Medicaid Services

(CMS) data and Department of Veterans Affairs (DVA) monitoring in the Veterans Affairs (VA) 

system have not detected any safety signals using historical comparator designs. Surveillance

conducted by international regulatory and public health partners have not detected a safety 

concern for ischemic stroke. There is no evidence of a safety signal for ischemic stroke in

7 Note: These surveillance activities did not include analyses to evaluate the effect of simultaneous flu vaccination; different 

formulations of COVID-19 mRNA bivalent booster vaccinations were used globally.
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Pfizer’s global monitoring of COVID boosters. No safety signals were detected for ischemic

stroke for primary series or monovalent boosters for Pfizer-BioNTech or Moderna vaccines in 

US and global monitoring.

In terms of further evaluation, CDC will continue to consult with other surveillance systems to

better understand the possible role of simultaneous high-dose or adjuvanted influenza 

vaccination with COVID-19 vaccination, as well as the possible decreased rate of stroke 

observed in the VSD in the 3 to 6 weeks following vaccination. CDC is in the process of chart 

reviewing a random sample of 100 cases across VSD sites and will continue to monitor VAERS.

CDC continues to recommend that everyone eligible for a COVID-19 mRNA bivalent booster or

influenza vaccine get vaccinated. CDC and FDA are engaged in epidemiologic analyses

regarding simultaneous vaccination with COVID-19 mRNA bivalent booster and influenza 

vaccines. 

v-safesm After Vaccination Health Checker

Tom T. Shimabukuro, MD, MPH, MBA (CDC/NCEZID) next presented an update on the vsafesm after vaccination health checker, including a brief overview of v-safesm, contributions of vsafesm to the COVID-19 response, data on historical and current participation in v-safesm, 

planning for the wind-down of the current system and the development of the next version of vsafesm, and continued safety monitoring of COVID-19 vaccines. As a reminder, v-safesm was

implemented in December 2020. It was designed to collect near real-time data by direct

outreach to vaccine recipients. It was initially conceived to rapidly collect basic safety data (e.g., 

primarily local and systemic reactogenic and health impacts) at the onset of the COVID-19

vaccination program to provide early data while other systems like VAERS and the VSD were 

accruing data. In addition, v-safesm identified vaccinated pregnant persons for possible

enrollment in the COVID-19 Vaccine Pregnancy Registry. It also was useful in rapidly collecting 

early safety data when authorizations and recommendations expanded to other age and risk

groups. It was quickly adapted to capture simultaneous administration of other non-COVID

vaccines (e.g., influenza vaccine). It was designed, built, and supported in collaboration with 

Oracle Health Services under a donation agreement with the Department of Health and Human 

Services (HHS). 

Enrollment in v-safesm is by self-registration on a smartphone, with any dependents added to a 

guardian’s account. Survey completion was prompted by text message reminders for “health 

check-ins,” which had links to online surveys. Call follow-up was performed on all participants

who reported a medically attended event. There was robust participation in its first year, with 9.3 

million participants and 131 million health surveys completed. Total participation to date has

included 10.1 million participants and 151 million health surveys completed. Most of the

registration and most of the health surveys occurred in the first year. v-safesm has been

particularly effective in characterizing the basic safety of COVID-19 vaccines during early 

vaccine introduction and following new authorizations and recommendations. v-safesm has 

successfully accomplished his mission and worked as intended. This graph shows participation

in v-safesm over time: 
13

Generally, registrations paralleled doses administered. As noted earlier, most new v-safesm

registrations and survey completions occurred in the first year of the vaccination program. Use 

has waned rapidly and has pretty low uptake at this point. Also noteworthy is that active

registration and doses administering paralleled early on when many doses were administered. 

Then there were peaks in doses administered largely representing new authorizations

and recommendations. However, there was not a corresponding surge in v-safesm uptake with 

these new registrations. There probably were a lot of early adopters early in the program, which 

is not totally unexpected.

It is important to understand what v-safesm is and is not. v-safesm was designed to rapidly 

monitor and assess common outcomes (e.g., local and systemic reactogenicity and health 

impacts)—the basic safety profile of the vaccine. It is not designed to be a signal detection or 

signal assessment system. Those systems are primarily VAERS, VSD, FDA's Biologics 

Effectiveness and Safety (BEST) System, and FDA, CMS, and VA active surveillance systems. 

In terms of the next step for v-safesm, the timing for the final registration and completing of

surveys will be announced soon. Follow-up will continue on reports of medically attended health 

events. The next generation v-safesm is under development. CDC plans to collect data on new

vaccines. Once developed and implemented, the new v-safesm will allow greater flexibility for 

surveys and use of CDC information technology (IT) infrastructure. It will be designed to permit

longer-term support for collecting data rapidly from a large number of vaccine recipients. vsafesm is one of the several complementary systems at CDC and one of many complementary 

systems that the USG uses to monitor vaccine safety. CDC’s standard established systems will 

continue to monitor and assess the safety of COVID-19 vaccines. That includes VAERS, the 

VSD, and the Clinical Immunization Safety Assessment (CISA) Project.

Discussion Points

Dr. Virginia Caine (NMA) observed that according to the VAERS data, Blacks have a 50% 

greater stroke incidence than their White counterparts and asked whether stroke incidence side 

effects data were broken down by race and ethnic populations to understand whether there 

would be higher risk among Blacks over the age of 65. 
14

Dr. Shimabukuro indicated that data on race and ethnicity are collected in VAERS, but because 

VAERS is passive, the data on these variables is dependent upon the reporters filling in that 

information. While the data are not analyzed by race and ethnicity, these data are collected. 

This information is also collected in the VSD, but the ability to analyze at that level is limited in 

the VSD because of small numbers. He acknowledged the importance and said that 

consideration can be given to exploring ways of getting better visibility on race and ethnicity. At 

least for the VSD RCA, race and ethnicity are not the primary variables in the RCA because the 

finer the data are sliced, the greater the small numbers problem.

While he was glad the signal had not persisted and that there would be continuing 

epidemiologic analyses regarding simultaneous vaccine with the high-dose influenza and

COVID bivalent booster, Dr. Sanchez asked if any changes were anticipated in the 

recommendation that they can be administered simultaneously or if there should be a 

cautionary note saying that there should be an interval of separation between the two.

Dr. Shimabukuro said he did not think the data were sufficient to conclude that there is a safety

problem for ischemic stroke with the Pfizer vaccine in this age group, or that there is a safety

problem with simultaneous administration of COVID and influenza vaccines. Additional work is 

being done. FDA has a study in progress and CDC and its VSD partners will continue to

evaluate the data. At this time, the feeling is that the data are not sufficient to conclude that 

there is a safety problem requiring make a change in recommendations.

Dr. Lee reflected on the importance of sustaining these vaccine safety surveillance efforts

beyond COVID-19. She reminded everyone that during H1N1, there was a similar effort in place 

akin to v-safeSM to monitor safety rapidly with the initial implementation of H1N1 vaccines, but it 

was difficult to sustain. With COVID-19, it was not clear how v-safeSM would be able to 

contribute. However, it has been quite impactful—especially for pregnant populations. She 

expressed gratitude to CDC for continuing to sustain important and complementary safety

surveillance tool for the future. It gave her confidence and she found it incredibly reassuring that 

based on the number of complementary systems at CDC for vaccine safety and in partnership 

with other federal agencies (FDA, DoD, IHS, VA, and others) that ACIP is are able to emphasize

the importance of vaccine safety to vaccination programs.

COVID-19 Vaccine Effectiveness Updates

LCDR Ruth Link-Gelles, PhD, MPH (USPHS/CDC) presented a summary of vaccine 

effectiveness data available from CDC studies, including VE of the original monovalent vaccines

and updated bivalent vaccines. This included presentations on updated estimates of VE of 

monovalent vaccines for symptomatic infection in young children aged 6 months–4 years 

(Pfizer-BioNTech) and 6 months–5 years (Moderna), as well as an update on monovalent and 

bivalent VE against severe disease in adults with and without immunocompromising conditions.

For background, she shared the national coverage estimates from CDC’s COVID Data Tracker8

for the primary series among young children showing that young children have the lowest

coverage for either a single dose or a completed primary series, with just over 10% for 1 dose

and 6% for the complete primary series in children 2 to 4 years of age. Coverage is even lower

among those under 2 years of age. Children vaccinated early may be meaningfully different

from those who remained unvaccinated, which may impact VE estimates.

8 https://covid.cdc.gov/covid-data-tracker/#vaccination-demographics-trends 
15

The Increasing Community Access to Testing (ICATT) platform includes community-based 

testing data from pharmacies and partners nationwide. It uses a test-negative design with selfreported vaccine history at the time of test registration. For these analyses, only children whose 

caregivers reported symptoms and who were between the ages of 3 and 5 years for the 

Moderna analyses and 3 and 4 years of age for the Pfizer-BioNTech analyses were included.

Children whose caregivers reported that the child being tested had immunocompromising 

conditions were excluded. These data are for tests from July 4, 2022 through April 8, 2023,

although the analysis start date varied depending upon the dose analyzed. This was a period 

when Omicron BA.4/BA.5 and XBB related sub-lineages predominated.

Looking at preliminary estimates of VE against symptomatic infection for monovalent Moderna 

vaccine among children 3 to 5 years of age, VE was 40% (95% CI: 25-52) for 1 dose or a partial 

series during the interval between the first and second doses. VE for the complete 2-dose 

primary series of Moderna was 47% (95% CI: 37-54) over the entire 2 weeks to 6 months after 

the dose. Broken down by time since dose, VE decreased from 61% (95% CI: 47-71) during the 

first 2 weeks to 1 month after the dose to 18% (95% CI: -6-37), with confidence intervals 

crossing the null during the 4 to 6 months after the dose. Looking at the same information for 

Pfizer-BioNTech in children 3 to 4 years of age for a 1-dose partial series, VE was 20% with a 

confidence interval that just crossed the null (95% ci: 0-36). For 2 doses, which for PfizerBioNTech also is a partial series, VE was 40% (95% CI: 28-50) in the interval between doses 2 

and 3. For 3 doses, a complete Pfizer-BioNTech primary series, VE was 27% (95% CI; 4-45) in 

the 2 weeks to 6 months after the dose. There was not enough statistical power to break down 

the Pfizer- BioNTech complete series estimates by time since last dose.

There are a number of limitations for this analysis. As noted earlier, vaccine coverage is low in 

children 5 years of age and under. When coverage is low, vaccinated children may be

meaningfully different than unvaccinated children, potentially biasing early VE estimates and

making the estimates less stable. The prevalence of prior infection among children is high.

Based on CDC seroprevalence data through December 2022, more than 92% of children 6 

months through 17 years of age had a prior infection. If unvaccinated children have protection

from prior infection, it may lead to an underestimation of VE. However, the prevalence of prior 

infection is so high that these estimates are likely to represent the current situation among

young children in the US. While the goal of the US COVID-19 vaccination program is to prevent 

severe disease, the ICATT platform estimates VE for symptomatic infection only. To date, low

vaccination coverage in this age group has prevented estimation of VE against more severe 

disease. However, other VE platforms may impact future ability to estimate VE in this group,

including against severe outcomes. Given this context, VE against symptomatic infection can

provide important insight into vaccine protection.

In conclusion, a complete monovalent primary series vaccination helped provide protection for

children 3 through 5 years of age against symptomatic SARS-CoV-2 infection for at least the 

first 3 months after vaccination. Some waning of the monovalent Moderna primary series

appears to occur by 4 to 6 months after the second dose. These patterns are similar to patterns

observed in older children and adults in the first months after vaccination. Waning of

monovalent Pfizer-BioNTech against symptomatic infection could not be assessed, but also is 

likely based on analyses in older children and adults. Children should stay up-to-date with

COVID-19 vaccines. CDC will continue to monitor VE in this age group, including against severe 

disease and for bivalent doses if possible.
16

Moving to updated estimates of bivalent VE against ED and urgent care (UC) encounters and

hospitalizations in adults 18 years of age and older, the VISION VE Network is a multi-state

network based on EHRs. Like ICATT, it uses a test-negative design with cases having COVIDlike illness and a positive PCR for SARS-CoV-2 and controls having COVID-like illness (CLI) 

with a negative PCR. VE is adjusted for age, sex, race, ethnicity, geographic region, calendar 

time, and local rates of SARS-CoV-2 circulation. Vaccination is determined via EHRs and state 

and city registries. In terms of the absolute VE of monovalent and bivalent vaccines against ED 

and UC encounters among immunocompetent adults among adults 18─64 years of age and 

≥65 years of age, for those who received only monovalent doses, roughly a year has passed 

since their last dose. For those receiving bivalent doses, the time since last dose is much 

shorter. For monovalent doses, there is little remaining protection. For bivalent vaccination, the 

trends across the age groups are similar with bivalent VE at 53% (95% CI: 48-58) for adults 

18─64 years of age and 61% (95% CI: 57-64) for adults ≥65 at 7 to 59 days after the first dose. 

Estimated VE declines by 120 to 179 days after the bivalent dose to 15% (95% CI: 2-26) for the 

younger group and 25% (95% CI: 16-34) for the older group.

For hospitalizations, there was some residual protection. In contrast to the ED, effectiveness of 

a monovalent dose was 21% (95% CI; 10-30) for younger adults and 25% (95% CI: 18-31) for 

older adults. For bivalent doses, trends were similar across age groups. However, there was not 

enough statistical power to interpret estimates for 120 to 179 days out from the bivalent dose in 

the younger group. In older adults, there was waning at a higher point estimate than against 

ED/UC encounters. Regarding absolute VE of bivalent booster doses against hospitalization 

among immunocompromised individuals ≥18 years of age, there was little remaining residual 

protection of the monovalent vaccine. VE estimates for bivalent vaccines started lower than for 

those of immunocompetent individuals at 30% (95% CI: 12-44), but the same patterns of waning

have not been seen in this group thus far.

To provide a snapshot of who is being hospitalized with COVID-19 and the VISION VE Network, 

it is important to note that this analytic population does not match the population used in the VA 

analysis precisely. It does give an overall sense of who is being hospitalized and who has

critical illness defined as “admission to intensive care or in-hospital death within the VISION 

Network. The median age is approximately 75 years. Eighteen percent of those hospitalized and 

24% of those with critical illness had an immunocompromising condition. This is compared to 

roughly 3% in the overall US population. Thirty percent of those in the hospital and 34% of those

with critical illness are entirely unvaccinated, which is particularly notable when considered

along with the median age of this population and the fact that in the US as a whole, 94% of 

those aged 65 and up have completed at least a primary series. Also notable is that 17% of 

those hospitalized and 15% of those with a critical hospitalization had received a bivalent

booster compared to about 43% of the overall US population over 65 years of age.

The next update is on data published by CDC in December 2022 looking at the effectiveness of 

the bivalent boosters against hospitalization in adults ≥65 years of age through the Investigating 

Respiratory Viruses in the Acutely Ill (IVY) Network, which is a multi-state VE platform that uses 

a prospective test-negative design. For this analysis, participants were enrolled from 25

hospitals in 20 states with hospitalization between September 8, 2022 and April 1, 2023. Note 

that this analysis includes data beyond what was published in the MMWR in December 2022.

Participants are adults hospitalized with COVID-like illness. Cases have a SARS-CoV-2 positive 

PCR or antigen test and controls are negative for SARS-CoV-2 and influenza by PCR. Models

are adjusted for age, sex, race, ethnicity, admission date, and HHS region.
17

In terms of updated IVY results among adults ≥65 years of age for absolute VE against 

hospitalization, comparing people with at least 2 monovalent doses but no bivalent dose to 

unvaccinated people, VE was 13% with a confidence interval crossing the null (95% CI: -9-30). 

This is consistent with the limited to no residual protection of the monovalent doses. Absolute 

VE of a bivalent booster followed a similar pattern, with high initial protection and apparent 

waning. Looking at the relative VE of a bivalent booster comparing individuals who received a 

bivalent booster to individuals with at least 2 monovalent doses but no bivalent booster, the 

additional protection offered by a bivalent booster was 60% (95% CI: 45-71) with waning 

apparent with more time since the dose. Note that as with the VISION estimates, the median 

time since last dose was over a year for monovalent only recipients.

Regarding the durability of monovalent VE protection against the most critical illness, invasive

mechanical ventilation (IMV) and death among adults ≥18 years of age in the IVY Network, this 

analysis assessed VE of 2 to 4 monovalent mRNA vaccine doses against IMV or death among

immunocompetent adults ≥18 years of age through January 31, 2023. Overall, this group is at 

approximately 8 months since their last monovalent dose. For the overall group, VE was 62%

(95% CI: 52-70) against critical illness. This does not vary substantially by age group. VE 

started at 76% (95% CI: 66-83) in the first 179 days since the last monovalent dose, with 

evidence of waning early on. However, that VE at a median of 455 days or about 15 months

since the last dose remained relatively high at 56% (95% CI: 36-69), showing the lasting 

durability of COVID-19 vaccines against the most critical illness. Looking at these same data 

broken down by time since last dose of 7 to 179 days or 180 plus days and number of 

monovalent doses received, there was a slight decline in VE by time since last dose, but 

sustained protection overall against the most critical illness. Substantial variation is not seen by 

number of doses received in either the earlier or the later period.

The results presented from both the VISION and IVY VE Networks have several limitations.

Regarding the estimates of absolute VE, if unvaccinated individuals are meaningfully different 

than vaccinated individuals, estimates may be biased. For interpretation of estimates of relative 

VE, residual protection from prior doses is an important consideration and likely varies by 

severity of outcomes studied. There is limited information on prior infection,

although just as with young children, rates of prior infection in adults and older children are

known to be high. Therefore, the VE estimates presented during this session represent a

snapshot of how well the vaccine is working under current conditions. Finally, VE against 

COVID-19-associated hospitalization from the IVY and VISION platforms represent individuals

hospitalized with COVID-19 disease, but may underestimate protection against critical illness.

In summary, current data from CDC VE platforms demonstrate that bivalent booster doses 

provide added protection compared to earlier monovalent doses against ED and UC encounters 

and hospitalizations in adults, though there is evidence of waning protection. For most adults,

both in the platforms shown and in the general population, more than a year has passed since 

they last received a monovalent COVID-19 vaccine. These individuals may have limited residual

protection against hospitalization and should receive a bivalent booster dose. However, results 

from the IVY analysis show durability of protection against the most critical COVID-19 disease

requiring IMV or causing death. CDC will continue ongoing monitoring of VE, including for all

outcomes of interest and for all authorized vaccines in the US, including Pfizer, Moderna, 

Janssen, and Novavax, with a focus on assessing new policy recommendations and VE in 

populations at higher risk of severe COVID-19 disease.
18

Discussion Points

Dr. Chen inquired as to why the original Wuhan strain was being included in the vaccines, given 

that there is evidence the more recent doses are more effective—certainly with the bivalent 

vaccines. This seemed like an opportunity to comment on thoughts about strain match and 

selection going forward for the bivalent versus monovalent vaccines for mRNA and other 

vaccine constructs as well. 

Dr. Link-Gelles pointed out that the goal of this presentation was to summarize what is known 

about currently available vaccines and that she would defer questions about strain selection and 

the make-up of current and future vaccines to later conversations among the ACIP and

VRBPAC.

Referring to Slide 7 regarding monovalent vaccine, Ms. Bahta asked whether there were any 

theories about why efficacy decreased or was not remarkable after the third dose of the Pfizer

BioNTech vaccine and there was no boost at all from the second dose.

Dr. Link-Gelles indicated that it was important to keep in mind that the confidence intervals

between the estimates overlap quite a bit so she was not sure it could be called a decrease. In 

addition, the time for follow-up is quite a bit different. For the 2-dose estimate, the analysis 

looked only at the interval before the third dose out to 3 months. The estimate for the third dose 

goes out to 6 months. That was because there were not enough children who received all 3 

doses, so there was not enough power to break it down by time since dose. Therefore, the third 

dose is getting dinged for having more extensive follow-up time. It is known from older children 

and adults that VE against symptomatic infection wanes by time since dose. If there were 

comparable follow-up times after the second and third doses, the point estimates probably

would be more comparable. 

Referring to Slide 14 regarding hospitalization among immunocompromised adults ≥18. Dr. 

Kotton observed that while there was some overlap in the various timeframes that showed 

potential waning, it was not as much as might have been expected. She asked if there were any 

thoughts about this, especially in the context of considering another bivalent booster for the 

immunocompromised population ≥18. 

Dr. Link-Gelles said she thought in part this was a precision issue, especially at the furthest

follow-up time where the confidence interval was quite wide and there may be missing waning

just because of that. In addition, the immunocompromised populations being studied in these 

platforms are fairly heterogeneous and includes the span of potential immunocompromise. It is 

known from earlier studies that the vaccine works much better in some immunocompromised

populations and worse in others, such as bone or organ transplant recipients. In this case, 

because of precision issues, there are not enough data to break it down by type of

immunocompromised. What this analysis was showing probably was the result of a relatively 

heterogeneous group combined with those that who probably are at highest risk of severe 

COVID being earlier adopters probably having different numbers of monovalent doses

previously received, and different times since those monovalent doses previously received.

What she would read from this comparison to immunocompetent individuals was that VE is

lower at the beginning in immunocompetent individuals and similar patterns of waning would be 

observed if broken down by some of the variables mentioned previously, which has not been 

possible due to precision.
19

Dr. Long observed that there did not seem to be much evidence of herd protection. With the 

effects of bivalent vaccine boosters apparently being modest and short-lived based on these 

analyses, it seemed the hope with this kind of vaccine and disease the hope would be to protect 

against death and mechanical ventilation.

Dr. Link-Gelles agreed that the goal of the COVID-19 vaccination program is to prevent severe 

disease, including hospitalization and the critical outcomes discussed. VE for symptomatic

infection has been shown in cases where there is a lack of data to show VE against more 

severe illness. This presentation showed VE for symptomatic infection in young children

because to date, there has not been sufficient statistical power to assess that against severe 

disease.

Recognizing that there is a very small proportion of the population vaccinated and that it is 

difficult to assess effectiveness with the small numbers, Dr. Long asked whether the vaccine 

manufacturers and possibly FDA could comment on post-market Phase 4 studies that might 

address effectiveness in these populations. There continues to be a strong need for additional 

data on the levels in durability of protection for children, pregnant people, and 

immunocompromised populations. 

Dr. Rituparna Das from Moderna responded that the effectiveness work is ongoing within the 

Kaiser Permanente Southern California Health System. Moderna presented some early data on 

bivalent effectiveness in adults during the January 2023 VRBPAC meeting and hopes to receive 

an update soon on pediatric VE and the immunocompromised. As noted, the ability to do this

will depend on the uptake in that system.

Alejandro Chevalier from Pfizer indicated that Pfizer also is working with Kaiser Permanente

Northern California and are seeking to bring the data soon.

Updates to COVID-19 Vaccine Policy: Considerations for Future Planning

Sara Oliver, MD, MSPH (CDC/NCIRD) first reviewed COVID vaccine uptake over time, pointing 

out that the overall population received vaccine shortly after recommendations have been

updated, but uptake overall has declined over time with additional vaccine recommendations. In 

terms of current vaccination coverage by vaccine and age group, 16.7% of the population

overall has received a bivalent booster dose to date, with higher coverage in older age groups.

However, even among adults ≥65 and over, over half of the population has not received a

bivalent dose to date. Regarding trends in variant proportions over time, the most recent 

surveillance shows that most isolates are related to the XBB sub-variant. Even with the newer 

variants, there has not been a larger increase in cases as seen in previous years. Looking at 

overall hospitalization rates by age from COVID-NET, the highest hospitalization rates continue 

to be among older adults.

Building on what was discussed in February 2023, the goal is simple recommendations.

Aspects of this include how frequently people should get a COVID vaccine and groups or 

populations who may benefit from possibly more than one vaccine a year. During this session, 

Dr. Oliver discussed steps toward simple recommendations, noting that this is a journey that 

likely will include several steps. In terms of a single formulation for mRNA COVID-19 vaccines, 

a single annual dose possibly will be needed for most individuals, with flexibility for vulnerable 

populations. It is important to note that many of the monovalent COVID-19 vaccine products

already have expired and others will expire soon. FDA has removed the authorizations from

monovalent mRNA COVID19 vaccine products and harmonization across the recommendations 
20

with the bivalent mRNA COVID-19 vaccines was discussed at the VRBPAC meeting in January 

2023 and the ACIP meeting in February 2023. Both advisory committees expressed support.

To summarize data that have been presented during previous ACIP meetings, the bivalent 

COVID vaccines are able to induce an immune response, whether given as a primary series in 

individuals who are previously unvaccinated or when given as a booster dose. When given to

unvaccinated children, the immunogenicity data of a BA.1 vaccine induced antibody titers to

BA.1 that were 25 times higher than the original monovalent vaccine. The percent of patients 

who reported local or systemic events were similar to or less than what was seen after the

monovalent vaccine. However, this may be a result of the larger percent of seropositive

participants in the bivalent vaccine group. There are limited data to directly compare COVID-19

outcomes after a monovalent versus a bivalent vaccine. Most studies showed an improvement 

in neutralizing antibodies for Omicron variants with a bivalent vaccine. However, it is difficult to 

correlate that improvement to defined clinical outcomes. When evaluating antigen cartography

that was presented in September 2022, the bivalent vaccines expanded the immune response 

and provided increased diversity in antibody response. Data from a United Kingdom (UK) study

found around a 10% increase in VE for COVID-19 infections with a bivalent vaccine. The 

transition will reduce the mRNA products from 11 vials to 5 vials and will eliminate the lookalike 

vials between the monovalent and bivalent products.

To summarize discussions from the last ACIP meeting, receiving COVID-19 vaccines continues 

to be important for prevention of COVID-19 severe disease, hospitalization, and death. 

However, many children and adolescents remain unvaccinated for COVID. COVID-19 vaccine

recommendations that are simple to implement may remove some barriers to uptake. Overall, 

ACIP was supportive of a transition of the mRNA COVID-19 vaccine primary series from 

monovalent to bivalent vaccines. As discussed earlier, FDA removed the authorization from

monovalent mRNA products. The BLAs are still in place, but the vaccines are either expired or 

have very limited doses in circulation. At this point, the bivalent mRNA COVID-19 vaccines are 

now authorized for all indications and there were no changes to the current language in the 

other COVID-19 vaccine authorizations, such as Novavax or Janssen COVID-19 vaccines. In 

terms of what this all means for CDC recommendations, a transition to bivalent COVID-19 

vaccines could simplify presentations, reduce errors, and allow continued access for vaccine

with the expiration of monovalent products. Bivalent mRNA COVID vaccines would now be

recommended for all indications.

The next step toward simple recommendations perhaps would be a single annual dose for most 

individuals. Looking at data from blood donors to assess the proportion of the population by type 

of immunity and how they have transitioned over time, the proportion has continued to decline 

over time. Overall, hybrid immunity has increased over time. Separated out by age groups, 

there are 2 things to note. The proportion with no prior infection or vaccination is low across all 

age groups in the most recent data. The proportion with hybrid immunity, which may at this point 

provide the strongest protection, is actually the lowest in that oldest age group. Highlighting

timing for increases in cases or hospitalizations, overall increases have been seen during the 

winter months, due to the emergence of new escape variants, or when both have occurred at

the same time.
21

To summarize previous discussions regarding the possibility of a single annual dose, future 

doses for most people would be an additional boost after prior infection, prior vaccination, or 

both. An update to the benefit-risk analysis shown in February demonstrated that time since the 

last COVID-19 vaccine dose may both increase the incremental benefits of a COVID vaccine 

and decrease the risk of myocarditis. As shown by VE studies, vaccine protection likely declines 

over time. Winter months and immune escape variants have impacted COVID-19 epidemiology.

It is known that a simplified annual recommendation could help reduce vaccine and message 

fatigue. A plan for a fall booster dose could provide added protection at a time when many

would be about a year from their last dose. The future epidemiology in SARS-CoV-2 virus

evolution could help determine the need for continued annual boosters.

Again, FDA authorized a single age-appropriate dose of mRNA COVID-19 vaccine for most 

individuals. A single age-appropriate dose of a bivalent Moderna COVID-19 vaccine is

authorized for individuals ages 6 years and older who are unvaccinated, or at least 2 months 

after receipt of any monovalent COVID-19 vaccine. A single age-appropriate dose of a bivalent 

Pfizer COVID-19 vaccine is authorized for individuals ages 5 years and older who are

unvaccinated, or at least 2 months after receipt of any monovalent COVID-19 vaccine.

School children nearly all have had prior infection, vaccine-induced, or hybrid immunity. The 

proportion with immunity is lower in the youngest age groups. Based on these and other data, 

some populations of young children likely still need a prime and a boost to optimize immunity. In 

addition, young children will continue to age into the vaccine recommendations at 6 months and 

could be SARS-CoV-2 naïve. Additional data are forthcoming to evaluate the benefits of a multidose primary series in all children ages 5 and younger, or if those recommendations could be 

simplified further. The WG looks forward to presenting a cost-effectiveness analysis in children

and additional antibody data in children during future ACIP meetings. In the pediatric population, 

FDA has authorized 1, 2, or 3 doses of a bivalent vaccine for children 6 months through 4 or 5

years. The number of doses depends on age and the number and type of prior COVID-19

vaccines received.

The overall implications for CDC recommendations are that a COVID-19 vaccine framework for

a single dose could be easy for COVID-19 vaccine providers to implement and for the public to 

understand. The current recommendation for a single dose may evolve over time and could

move to an annual recommendation. With these updates, a single bivalent dose would be

recommended for everyone ages 6 years and over. For most people, the implication of this 

update means no change, and. the actions taken after this are exactly the same. If someone 

has not received a bivalent vaccine yet, they are recommended to receive one regardless of 

their previous vaccine history. Children 6 months through 5 years of age would receive at least 

2 COVID-19 vaccine doses, including at least 1 bivalent vaccine. Detailed guidance for this will 

be published in the Interim Clinical Considerations.

In terms of flexibility for vulnerable populations, the rates of hospitalization for those 65 years of 

age and over have seen several increases over the past year. Unlike what was seen previously 

in the pandemic, these increases have not been nearly as high in the other younger age groups 

as they were earlier. However, rates of COVID-19 death by vaccination status among older

adults 65─74 years of age and ≥80 years of age are highest among the unvaccinated and 

lowest are among those with an updated or bivalent booster dose. Many adults who already

received a bivalent booster dose were eager for the option to receive another one. In a survey 
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of boosted adults in January,9 over half said that they were awaiting new guidelines for 

additional doses and 86% said that they felt it was an important or top priority to receive 

additional doses. While it is known that many in the population are experiencing vaccine fatigue, 

there is a subset who are eager to continue to receive additional doses.

To summarize overall what was discussed in February, it is known that older adults continue to 

have higher rates of hospitalization than younger adults. Among older adults, vaccination rates

with bivalent COVID-19 vaccines remain low and it is known that it is critical for older adults to

be up-to-date on current recommendations, including receiving a bivalent booster. ACIP

discussed that at the time, the data were insufficient to support a routine recommendation for

older adults to receive a COVID vaccine dose every 6 months long-term, but acknowledged that 

the population may continue to be more vulnerable to severe COVID-19 and likely needs

flexibility with COVID-19 vaccine recommendations. Updates from FDA’s authorizations for 

adults ≥65 years of age are that a single dose of a bivalent mRNA COVID vaccine, either Pfizer

or Moderna, may be administered at least 4 months following the first bivalent dose. In terms of 

implications for CDC recommendations, bivalent COVID-19 vaccines continue to provide 

protection against severe disease and rates of hospitalization or death among adults who have 

received a bivalent booster continue to be low. However, some older adults may benefit from an 

additional updated COVID-19 vaccine dose prior to future recommendations for updated 

vaccines this fall. Adult ≥65 years of age may now choose to receive another updated COVID19 vaccine dose if it has been 4 months since their first bivalent dose. 

For immunocompromised persons, data presented in February showed that 

immunocompromised adults can have a less robust immune response to COVID-19 vaccines.

Unfortunately, there are no currently authorized prophylactic monoclonal antibody products for 

populations at highest risk for COVID-19. ACIP discussed that while the data were insufficient to 

support a routine recommendation for people who are immunocompromised to receive a COVID 

vaccine every 6 months long-term, they acknowledged that this population continues to be 

vulnerable and needs flexibility with COVID-19 vaccine recommendations. FDA has provided 

that flexibility. For people who are immunocompromised, additional doses have been 

recommended previously and current updates continue to allow additional protection to a 

vulnerable population. Updates also allow flexibility to adjust to an individual’s specific

circumstances, including timing of immunosuppression as well as the possible need for revaccination after particular events (e.g., stem cell transplant). Additional guidance is to be

published in Interim Clinical Considerations. People who are immunocompromised may choose 

to receive another updated COVID-19 vaccine dose and have the flexibility to receive additional 

doses based on their clinical circumstances.

To recap, steps toward the goal of simple recommendations include the single formulation 

mRNA COVID-19 vaccines and a single (possibly annual) dose for most individuals, with 

flexibility for vulnerable populations. However, this cannot be achieved in a single action, so it is 

important to acknowledge that future steps may be possible. While the updates during this 

session were focused on mRNA vaccines, it may be possible to simplify all COVID-19 vaccines. 

While looking to the possibility of updated vaccines this fall, the WG will continue to evaluate

data-driven ways to simplify the pediatric program and present related data during upcoming 

meetings. As always, the goal will be to continue to work toward a goal of flexibility and simple 

guidance.

9 KFF COVID-19 Vaccine Monitor: January 2023. https://www.kff.org/coronavirus-covid-19/poll-finding/kff-covid-19-vaccine-monitorjanuary-2023/ Accessed February 7, 2023
23

In summary, COVID-19 vaccines continue to be the most effective tool available to prevent

serious illness, hospitalization, and death from COVID-19. Simple recommendations are easier 

to communicate, which may improve uptake. It is anticipated that an updated fall vaccine could 

be available. The WG will continue to review data to inform possible recommendations. Based 

on available data at this time, it is anticipated that there would be benefits of COVID-19 

vaccines this fall. Updates to COVID-19 vaccine policy also can acknowledge the possibility of 

future recommendations. For most individuals, the current doses needed remain unchanged. A 

single bivalent vaccine is recommended and there could be an updated vaccine and

recommendations this fall. In direct response to feedback from previous discussions, there is 

flexibility for vulnerable populations in the current recommendations. Young children continue to 

be recommended for multiple doses for the prime/boost immune response. The WG will

continue to review additional data to optimize those recommendations.

To summarize the WG discussions overall: the WG will continue to review data and evaluate the 

COVID-19 vaccine program in the context of evolving epidemiology. To date, the COVID-19 

Vaccine WG has had 112 calls in which they have reviewed the data and discussed the COVID19 vaccine program. Early COVID-19 vaccine recommendations were made in light of a highly

susceptible immune-naïve population who had limited treatment options. Increases in 

population-level immunity through vaccine and infection, SARS-CoV-2 virus evolution, 

availability of antiviral treatments, and the review of COVID-19 epidemiology and hospitalization 

rates can lead to evidence-based updates in vaccine policy. This does not change decisions

that were made then but highlights that the program can continue to evolve as these data

evolve as well. Work will be ongoing to review additional data and continue efforts for 

simplification. When reviewing the totality of the data, the WG was supportive of simplified

recommendations and flexibility for vulnerable populations.

Updates to Interim Clinical Considerations for Use of COVID-19 Vaccines

Evelyn Twentyman, MD MPH (CDC/NCIRD) presented updates to the Interim Clinical 

Considerations for the use of COVID-19 vaccines that are anticipated as a result of the 

authorized revisions the previous day. First, these new recommendations are simple and 

singular for most people. The previous recommendations were for people ages 6 through 11 

years without immunocompromise, including specific recommendations for a primary series and 

booster, with variation by age and by product. The new recommendation for people aged ≥6

years without immunocompromise who have not yet received a bivalent mRNA dose is 

extremely simple: receive one bivalent mRNA dose regardless of COVID-19 vaccination history.

The good news is that vaccination is complete for people who already have received a bivalent 

Pfizer or Moderna mRNA dose and no doses are indicated at this time.

The new recommendations also offer flexibility for people at higher risk. One of the groups of 

people at higher risk of severe COVID-19 disease is people ages 65 years and older. People 

ages 65 years and older who have not yet received a bivalent mRNA dose are recommended to 

receive that dose. Additionally, they have the option of receiving an additional bivalent mRNA 

vaccine dose when it has been at least 4 months following their first bivalent mRNA dose. That 

means that those aged 65 years and older who have already received a bivalent mRNA dose, 

for example, who received their updated booster when they were authorized in September 2022 

or sometime thereafter, are already up to date. Vaccination is complete. 

With the new flexible recommendations, they have the option of receiving an additional bivalent 

mRNA vaccine dose when it has been at least 4 months following the initial bivalent dose. There 

also is flexibility for people at higher risk of severe COVID-19 disease due to

immunocompromise. For those people aged 6 years and older who have already received a 
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bivalent mRNA dose, an optional additional bivalent mRNA dose may be administered at least 2

months after their first bivalent mRNA dose and additional bivalent mRNA doses may be 

administered as needed. The changes additionally offer customized recommendations for 

young children as illustrated here. The new recommendations are customized by COVID-19 

vaccination history such that all children receive at least 2 vaccine doses in total, including at 

least 1 bivalent dose. This flow chart was developed to depict how to easily determine what 

customized recommendation is relevant to a child given their personal COVID-19 vaccine 

history. For the Interim Clinical Considerations to be posted to the CDC website, a complete 

table has been developed of the recommendations for vaccine doses moving forward, given any 

particular history of COVID-19 vaccination:

The other group of children who have customized recommendations are 5-year-olds. These 

recommendations are extremely similar to those for children ages 6 months through 4 years:
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To summarize it means to be up-to-date with COVID-19 vaccines in the context of the new 

recommendations, adults and children aged 6 years and older are up-to-date with COVID-19 

vaccines if they got a bivalent (updated) COVID-19 vaccine. Children 6 months through 5 years

of age who received the Pfizer-BioNTech COVID-19 vaccine are up-to-date if they are 6 months 

to 4 years of age and got at least 3 COVID-19 vaccine doses, including at least 1 bivalent 

(updated) COVID-19 vaccine dose or they are 5 years of age and got at least 1 bivalent 

(updated) COVID-19 vaccine dose. Children 6 months through 5 years of age who got the

Moderna COVID-19 vaccine are up-to-date if they got at least 2 Moderna COVID-19 vaccine 

doses, including at least 1 bivalent (updated) COVID-19 vaccine dose. Persons may be eligible 

for additional COVID-19 vaccine doses if they are 65 years of age and older and got their first 

bivalent (updated) COVID-19 vaccine booster 4 or more months ago and/or are moderately or 

severely immunocompromised and received a bivalent (updated) COVID-19 vaccine booster 2 

or more months ago. Someone who is unable or chooses not to get a recommended bivalent

mRNA vaccine will be up-to-date if they got the Novavax COVID-19 vaccine doses approved for 

their age group.

In terms of implications for vaccine providers, the new recommendations result in fewer total 

COVID-19 vaccine products in use, which might be very helpful for vaccine providers. There will 

now be 5 total bivalent products in use and 1 monovalent product in use. The supply of the 1 

remaining monovalent COVID-19 vaccine will be expired on May 6, 2023. Additional help for 

providers is on the way. CDC is working to serve providers the very best way possible. Interim 

Clinical Considerations are being updated with comprehensive tables of vaccine doses and 

dosages indicated for each age group, and by history of COVID-19 vaccines received for 

children aged 6 months through 5 years. CDC is working to revise additional clinical guidance

materials and will present these new recommendations and their implications for providers in 

greater depth during an upcoming Clinician Outreach and Communication Activity (COCA) call 

on May 11, 2023.

In terms of implications for public health, one of the most important messages is that although 

the new recommendations are simplified and although everyone ages 6 years and older will 

now be up-to-date following receipt of an updated mRNA vaccine, most people in the US have 

not yet received an updated mRNA vaccine. Just 16.7% of the entire US population and just 

over 20% of adults or 4 out of 5 adults have not yet received a bivalent mRNA vaccine and are 

not up-to-date with COVID-19 vaccination at this time. Bivalent COVID-19 vaccine coverage

tends to decrease with decreasing age. Unfortunately, coverage is not even 50% among people 

ages 65 years or older who may be at higher risk of severe COVID-19 disease because of their 

age. Unfortunately, racial disparities in receipt of bivalent mRNA vaccines persist. Bivalent 

COVID vaccine coverage is lowest among Black, non-Hispanic, Hispanic/Latino, and Native 

Hawaiian or other Pacific Islander populations. It also is important to point out that bivalent 

COVID-19 vaccine coverage is lower among those with lower income. It is evident that providing 

these vaccines free of cost to the recipient has not yet resulted in equitable coverage by 

income. Unfortunately, bivalent COVID-19 vaccine coverage is also lower among those without 

health insurance. It is important to underscore here that a person does not need to have health

insurance in order to receive a bivalent COVID-19 vaccine. It does appear that there is still work 

left to be done in achieving equitable coverage for those without health insurance.

To provide some reflections and next steps, COVID-19 vaccines continue to be the most 

effective tool to prevent serious illness, hospitalization, and death from COVID-19. However, 

uptake of the updated bivalent COVID-19 vaccines is not yet equitable and remains generally 
26

low. Simple recommendations are easier to communicate, which hopefully may improve vaccine 

uptake. CDC is continuing to work toward additional materials for vaccine providers, clinicians, 

and the general public to make it easy for everyone to get up-to-date and stay up-to-date with 

COVID-19 vaccines. 

Discussion Points (Oliver & Twentyman)

Ms. Bahta asked whether ethnic and racial background information related to hospitalization 

and death are available and expressed concern that there might be a missing gap of individuals 

who are vulnerable between 50 to 65 years of age.

Dr. Oliver recalled a presentation in February from the COVID-NET team, which is where those 

data come from at CDC. While she did not remember specifically whether those data showed 

race and ethnicity, she will engage in discussions looking forward to future meetings to 

determine whether additional data can be provided on that.

Based on the comments that have been made via the Federal Registry, Ms. Bahta pointed out 

that it is important to understand why the recommendations are not being updated and 

especially why there is no booster for Novavax. While Dr. Marks addressed this, she thought it 

was important to re-explain that.

Dr. Twentyman indicated that there is a Novavax booster that is authorized in some situations,

specifically including among those who are unable or unwilling to receive a bivalent mRNA

vaccine dose and who have not received previous booster doses. This is part of the

authorization of that vaccine dose and is why it is stated as such. In terms of updating the 

Novavax vaccine itself, she called upon the sponsor to comment.

Dr. Raburn Mallory, Novavax, indicated that they are working to provide an updated vaccine for 

the upcoming full winter season. They have been engaged in discussions with the FDA and 

other regulatory authorities about what kind of updates might be made to the vaccine.

Dr. Kotton asked whether the FDA could provide any additional explanation for children who are 

immunocompromised regarding the number of vaccine doses that they can receive, which 

seemed somewhat different from what ACIP had been thinking. In addition, she asked whether 

there would be additional guidance from FDA or CDC through Clinical Considerations. While 

she understand that the intent was to provide an individual clinician flexibility with some of the 

more extenuating circumstances, she wondered if there would be any specific language 

provided regarding that, because as an immunocompromised host provider, she was not 

necessarily entirely clear on what the flexibility actually would provide.

Dr. David Kaslow, FDA, indicated that immunocompromised children and adults can receive an 

additional bivalent dose after they have gotten their first bivalent dose. FDA has provided 

flexibility for additional doses at the discretion of the HCP and taking into consideration an 

individual’s clinical circumstances. 

Dr. Twentyman clarified that Moderna recipients ages 6 months through 5 years of age have the 

option to receive further additional doses of bivalent Moderna COVID-19 vaccine as informed by 

the clinical judgment of a HCP, personal preference, and circumstances. Those ages 6 years 

and older who received Moderna also have the option to receive further additional ageappropriate doses of bivalent Moderna COVID-19 vaccine as informed by the clinical judgment 

of a HCP, personal preference, and circumstances. Pfizer recipients ages 5 years and older
27

have the option to receive further additional age-appropriate doses of bivalent Pfizer COVID-19 

vaccine informed by clinical judgment, personal preference, and circumstances. Novavax

recipients ages 12 years and older have the option to receive further additional age-appropriate

doses of bivalent mRNA COVID-19 vaccine informed by the same considerations. Children 6 

months through 4 years of age who are immunocompromised who received Pfizer are not 

perceived to be authorized at this time.

Dr. Marks emphasized that the FDA has to make decisions based on data and there were not 

sufficient data to support the additional dose. Updates will be made when data are available. 

That means that immunocompromised children 6 months through 4 years of age who had a

prior Pfizer dose cannot receive additional vaccine doses moving forward until such time as 

FDA has the data, which is anticipated to be toward the fall vaccination campaign once strain 

selection is decided.

Dr. Kotton stressed that this potentially leaves this immunocompromised vulnerable population

at higher risk for at least the next 6 months, which sounded potentially devastating for a highrisk immunocompromised population. Certainly, during the pandemic there have been times

when the best decisions have been made at the time based on the preponderance of data in the 

interest of public health. She spoke strongly in favor of trying to protect this vulnerable pediatric 

population.

Dr. Marks indicated that FDA is happy to take this into consideration and to speak with their 

CDC colleagues.

Regarding the bivalent Moderna being a lower dose than the primary series, Dr. Lee asked what 

the potential impact would be now that the lower bivalent dose would be allowed for use as a 

primary series even though an additional dose is allowed. Immunocompromised children and 

adult patients are presenting with severe consequences and have been hospitalized for

prolonged periods of time. For the immunocompromised population, there are not good choices 

right now or the data to support that it will be possible to optimally protect that population. Given 

that, she asked what guidance FDA would give providers who are caring for these patients.

Dr. Marks replied that they allowed the additional dose for Moderna because of the way 

previous doses were administered and the situation they were in. It was a challenge to sort out 

what would be best to do, given the various doses of the vaccine that were used in the initial 

series and in subsequent ones. FDA will take this under advisement.

Dr. Lee emphasized the need to highlight the gap that Dr. Kotton identified and provide some 

guidance to clinicians about how to manage these patients because right now, there are not 

optimal ways to protect those who are immunocompromised who are 5 years of age and 

younger.

Dr. Das, Moderna, responded that the primary series is 25μg for children, but the booster dose 

is 10μg for children 6 months to 5 years of age. The 10μg bivalent booster dose is also the dose 

for 6 years of age plus. Dr. Lee noted that the question would be whether to provide the 25μg

dose for those who might be immunocompromised if they are felt to need the additional doses 

versus the one that is now approved for those 6 months to 5 years of age.

Dr. Sanchez expressed appreciation for the flexibility, echoed what had been said about

immunocompromised children, and agreed that clarification was needed. Given VE in 

immunocompetent children with the Pfizer and Moderna products, he would think that 
28

immunocompromised children need further dosing and would appreciate not only further, but 

also more protection in that age group. In terms of scheduling, the bivalent dosing of 10μg was 

still confusing to him.

Dr. Twentyman indicated that this would be addressed in the forthcoming Interim Clinical 

Considerations. CDC is creating a table of precise dosage by both microgram, intervals by age, 

and COVID-19 vaccine history so that providers will be able to look up exactly where their 

patient is sitting on the table and provide exactly the dosage indicated from the vial indicated. To 

speak to the Moderna issue, the chart indicates that children 6 months to 4 years of age who 

have not previously received COVID-19 vaccine are recommended to receive 2 doses of 

Moderna COVID-19 bivalent vaccine at a dosage of 25 μg from the dark blue cap gray label 

bordered vial at an interval of 4 to 8 weeks between Dose 1 and Dose 2. That is just one 

example, but the plan is to provide this guidance for every age and by history where relevant 

among children ages 6 months through 5 years. The 10μg dose remains in use for children with 

a history of receipt of 2 doses of monovalent Moderna COVID-19 vaccines. In other words, that 

recommendation has not changed from the previous recommendation, and they can receive the 

10μg dose from the existing booster dose vial for that age group.

Dr. Marks, FDA, clarified that for the Moderna vaccine, children between the ages of 6 months

and 4 years have received 2 doses at 25μg. As in some adult situations, there can be a third 

dose given to the immunocompromised at the same 25μg dose. A third 25μg dose of Moderna 

may be given in that population. Immunocompromised children who have not received any

doses could receive up to the 3 doses of Moderna at 25μg each. That information is included in 

the Fact Sheet.

Dr. Caine pointed out that the Biden Administration has a Bridge program for the 30 million 

uninsured adults, and there is an effort to get funding for the vaccine for adults. One of the 

slides showed that only 9% of Blacks overall have had bivalent COVID-19 vaccine. She asked 

whether there are any recommendations and/or funding from ACIP for community-based 

organizations (CBOs) engaged in outreach to get folks vaccinated. She is concerned about 

those who are not connected to a medical home such as FQHCs or providers and about how to 

get them connected to a medical home. Also concerning is that there has been a substantial 

increase in undocumented immigrants.

Dr. Peacock indicated that throughout the pandemic, a fairly large amount of funding has been 

provided to CBOs and various state and local health departments to focus on this type of work. 

One of the activities that CDC has funded is through the Partnering for Vaccine Equity (P4VE)

program. That is COVID-19 supplemental funding that is still in place and is scheduled to go

through FY24. CDC is continuing to work with CBOs, which is a critical need. Overall, there has 

been fairly low uptake of updated vaccine and a lot of work needs to be done to improve 

confidence and access for these vaccines.

Dr. Hackell seconded the comments about addressing pediatric patients whose age group

changes, especially during the Moderna primary series because the dose is different.

Pediatricians often are asked a lot of questions by families, parents, and grandparents. 

Anticipating a possible update in the vaccine in the fall and thinking about whether the optional 

second booster should be received now, there could be an impact on eligibility for a booster in 

the fall if the composition of the vaccine changes.
29

Dr. Oliver emphasized that changes are being made to the recommendation in anticipation that 

there still may be additional changes this fall. Overall, especially for children, the additional

doses that would be recommended would be for immunocompromised people. This would be up 

to the clinician, but if there is a desire and potential benefit, especially based on the level of 

immunocompromise, then she would encourage someone to get all available doses. It is not 

anticipated that getting a dose now would preclude somebody from getting a dose in the fall.

Reasonably healthy and perhaps older adults may want to wait until the fall, which is an option.

To clarify some continuing confusion, Dr. Twentyman explained that the transition from the era 

of monovalent mRNA vaccines to bivalent mRNA vaccines is slightly different for 5-year-olds 

because these children were previously recommended to receive either 2 or 3 primary series 

doses and then at least 1 bivalent dose. For 5-year-olds who have started the Moderna series, 

there are now customized recommendations to make sure that they all receive at least 2 

vaccine doses in total, including at least 1 bivalent dose. Pfizer recipients who have turned age 

5 who received Pfizer or who will receive Pfizer have the very simple recommendation of

receiving a single bivalent dose.

PUBLIC COMMENT

Overview 

The floor was opened for public comment on April 19, 2023 at 1:30 PM ET. Given that many 

more individuals registered to make oral public comments than could be accommodated during 

this meeting, selection was made randomly via a lottery. Dr. Lee provided a gentle reminder that 

the ACIP appreciates diverse viewpoints that are respectful in nature and issue-focused. The 

comments made during the meeting are included in this document. Members of the public also 

were invited to submit written public comments to ACIP through the Federal eRulemaking Portal 

under Docket ID CDC-2023-0028. Visit http://www.regulations.gov for access to the docket or to 

submit comments or read background documents and comments received.

Public Comments

Donna Treubig

Licensed Child Care Provider

Family Traditions Child Care

Thank you. Hello. I am a licensed childcare owner/provider. I have worked very hard over the 

last 3 years and continue to work to protect the very young children I care for, including my

young grandchildren, from this virus. I have no conflicts. I'm also a proud member of Protect 

Their Future, a non-profit grassroots advocacy organization made up of parents, doctors, and 

scientists dedicated to ensuring that children are prioritized regarding the development of

vaccines. While I am a member, the following comments are my opinions. Our children need

your commitment to the early approval of the next round of fall vaccines before school starts in 

August. We need all children, including children under 5, to be vaccinated and have immunity

before starting school and daycare this fall. Please simplify the process. Families across the

country are actively looking to vaccinate their young children, but pharmacies will not administer

them and pediatric offices cannot manage a large stock of vials. All vaccine trials and next 

generation solutions should include all age groups simultaneously. We know that the vaccines 

are safe and effective. We also know from the data that children under 1 are at a higher risk for

COVID complications. Babies cannot wear a mask to protect themselves. Even based on 
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today’s discussion, please do not continue to leave them behind. It would be beneficial for those 

who haven't been infected, pregnant women, people with high BMI, and others to have access

to another bivalent booster before the late summer spike. There shouldn't be an age range or 

immunocompromised requirement to get a second bivalent booster today. It is too early to move

to a once-a-year flu shot-type schedule for COVID. COVID is still mutating. The vaccine

manufacturers need to be ready and free to produce a variant specific booster that is quickly 

available to all age groups. Thank you very much.

Ms. Crescent Martin

Pregnant Person

Good afternoon and thank you for the chance to comment today. I urge the ACIP and CDC, in 

coordination with colleagues at FDA as needed, to immediately grant pregnant people

permissive access to an additional COVID booster based on their pregnancy status. Recently, 

the WHO updated its recommendations to include pregnant people as a high priority group and 

to recommend that pregnant people receive an additional booster dose if their last dose was 

more than 6 months ago. I was heartened to hear Dr. Sara Oliver state at the February ACIP 

meeting that a deeper dive into the emerging data on vaccination among pregnant individuals,

with a view towards assessing what data is needed to make recommendations for that

population, is among CDC’s top priorities for upcoming meetings. But I'm here to remind you 

that people who are currently pregnant do not have the luxury of waiting for full consideration of 

all of the emerging data. I received a bivalent booster as soon as I could get an appointment in 

September—more than 7 months ago. I'm currently in my third trimester of pregnancy and I 

recently received a Tdap booster as recommended to protect my infant against whooping

cough. However, under current restrictive US authorizations, I'm not eligible to receive an

additional COVID booster to maximize the maternal antibodies I could be passing on to my 

infant. These antibodies could help reduce her risk of serious COVID complications before she 

is eligible for her own vaccination. For context, this is my second pandemic pregnancy. My first 

pandemic baby was born in Summer 2020, a truly scary time to be pregnant, before any 

vaccines were available. My family tried hard to shield my son from getting COVID until after he 

was finally eligible to be vaccinated in June 2022. In large part, our concerns were about the 

unknown long-term consequences of infection with a novel pathogen, especially with a naïve 

immune system. In 2023, we're now fortunate to have the tools of vaccination and so it should 

be much easier to protect this pandemic baby. However, the current move to an annual

vaccination schedule does not have enough flexibility to optimally protect the vulnerable groups

of pregnant people and infants under 6 months. As we wait for sufficient evidence to support an 

affirmative policy recommendation that a COVID booster is absolutely necessary in each

pregnancy, we do have very strong safety data. The currently available evidence suggests that 

the known and potential benefits of an additional booster are likely much higher than the known 

and potential risks. It would be a reasonable choice under a shared clinical decision-making

model for a pregnant person to choose an additional booster dose during pregnancy. CDC and 

FDA policy should not stand in the way of that decision, but instead should ensure that pregnant 

people have authorized access to additional booster dose if they wish to receive one. This, of 

course, is in addition to continuing to promote and provide access to vaccination for the many, 

many pregnant people who are not otherwise up-to-date. Thank you for your consideration and I 

look forward to hearing your discussion this afternoon.
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Dr. Jonathan Vigh

Project Scientist

National Center for Atmospheric Research

Thank you so much, Dr. Lee and ACIP members. Thank you for the opportunity to provide input 

on this very important subject. I'm a Project Scientist at the National Center for Atmospheric 

Research in Boulder, Colorado. I'm also a wildfire survivor. My family lost their home in the 

Marshall Fire. My 2 children attend elementary school here in Colorado and there has been a 

frightful amount of illness at their school this year, including COVID, RSV, flu, and strep.

Although no one in my family has tested positive for COVID so far, my son has been sick for 

weeks and we worry he could be suffering from post-viral syndrome. I've learned that resilience 

is vital, and that health cannot be taken for granted. I had Moderna for my first 3 vaccinations. 

After my second shot, I experienced a strong reaction which included fever, malaise, heart 

palpations, and chest pain. My first booster was only somewhat better. It was miserable to have 

to miss a day of work each time I got vaccinated. Last fall, I was due for my second booster, so I 

decided to try Novavax. The difference was night and day. The only side effects I experienced 

were a sore arm, a slight tingle in my scalp, and feeling a little tired in the evening. I was able to 

work the next day and for me, Novavax was a game changer. From everything I've heard, I 

understand that Novavax's monovalent vaccine has effectiveness on par with the bivalent 

vaccines. Recent real-world data shows that the mRNA protection starts strong and begins 

fading as early as 4 months. In contrast, Novavax offers durable, lasting protection and 

excellent protection against severe disease with fewer side effects. Also, many people suffering 

long-COVID have reported that Novavax improved their symptoms. The weight of evidence that 

we have in hand shows that Novavax is an effective and safe vaccine. Therefore, it is

inexplicable why the current guidelines make it nearly impossible for Americans to get Novavax 

as a second booster. I have not seen any scientific justification that supports this restriction. I'm

asking for 4 changes to vaccine immunization practice today: 1) Please allow all age groups to 

get vaccinated more than once per year, if desired; 2) Please speed up the timeline for kids 

under 12 to be able to get Novavax. I would like my kids to get it; 3) allow kids to get their 

booster a full month before the school year starts; and 4) Please, please change the guidelines 

to allow people to get Novavax without regard to their previous vaccination history. We won't 

achieve full vaccine equity until all Americans have the freedom to choose the vaccine that is 

best for them. Once we achieve this, I believe that we will see improved uptake of boosters. 

This will move the needle toward stopping transmission and finally ending this pandemic. Thank 

you very much.

Ms. Gwendolyn Kull

Attorney & Contributing Author

Brownstone Institute

Thank you. My name is Gwendolyn Kull, I'm an Attorney and a Contributing Author for

Brownstone Institute. I'm here today to speak about the policy requiring COVID-19 vaccination 

for foreign travelers to the United States. And for those of you who might not be aware, the CDC 

has an Amended Order mandating that all travelers, non-citizen, non-immigrants, to the United 

States be vaccinated before boarding an airplane. If this policy were truly for preventing

disease, shouldn't we instead mandate testing? This policy has failed at its purpose and is 

costing thousands, precious time with their family members, and the US economy billions in 

revenue. As of August 19, 2022, the CDC public policies should not differentiate by a person’s 

vaccination status because of breakthrough infections. Yet this policy continues, leaving those 

of us harmed by it to question why. Vindictive punishment for the exercise of medical autonomy 

or religion? The CDC has a duty to the American public and the US Constitution to rescind the 
32

policy regardless of President Biden's proclamation because it is unconstitutional. It is an

unlawful delegation under Title 3 since Director Walensky was not appointed through Senate 

confirmation. It is not rationally related to the purpose of disease prevention since vaccines do 

not prevent the disease, and it further causes families to be separated. It oversteps authority

vested by Congress under the Administrative Procedures Act by creating additional 

requirements for entry into the United States than are actually legislated under Title 8, Section 

1182a, which only requires proof of vaccination against vaccine-preventable diseases prior to 

entry. Even if the vaccine did prevent disease, the policy is still ineffective because it doesn't 

apply to Americans who can travel nearly anywhere in the globe unvaccinated, free to transmit 

the disease. In reality, the policy fails because the vaccines do not prevent disease and it allows 

people with active COVID infections to fly to the US so long as they present proof of

vaccination. As a result of this policy, bi-national families have been kept apart—some for more 

than 3 years. Unvaccinated visa holders living in the United States have been trapped here for 

fear they will be denied re-entry and lose their jobs or education. Tourists choose non-US 

destinations. The vaccine is now also senselessly on the immigration schedule for adults and 

children, again violating 1182a and the PREP Act. Probable reciprocity is not maintained with 

other nations and the US lost nearly $100 billion between lost tourism revenue and the cost of 

enforcement in the last year alone. Stop wasting resources and taxpayer dollars on this moot

and unlawful policy that's causing real harm to innocent, healthy people while not preventing 

transmission. Resend the amended order implementing Proclamation 10294. Thank you.
33

CERTIFICATION

Upon reviewing the foregoing version of the April 19, 2023 ACIP meeting minutes, Dr. Grace 

Lee, ACIP Chair, certified that to the best of her knowledge, they are accurate and complete.

Her original, signed certification is on file with the Management Analysis and Services Office 

(MASO) of CDC.
34

ACIP MEMBERSHIP ROSTER 

CHAIR 

LEE, Grace M, MD, MPH 

Associate Chief Medical Officer for Practice Innovation 

Lucile Packard Children’s Hospital 

Professor of Pediatrics, Stanford University School of Medicine 

Stanford, CA 

Term: 8/4/2021 – 6/30/2023

EXECUTIVE SECRETARY 

WHARTON, Melinda, MD, MPH

National Center for Immunization and Respiratory Diseases

Centers for Disease Control and Prevention

Atlanta, GA

MEMBERS 

BAHTA, Lynn, RN, MPH, CPH 

Immunization Program Clinical Consultant 

Infectious Disease, Epidemiology, Prevention & Control Division 

Minnesota Department of Health 

Saint Paul, Minnesota 

Term: 7/1/2019 – 6/30/2023

 

CHEN, Wilbur H, MD, MS, FACP, FIDSA 

Professor of Medicine 

Center for Vaccine Development and Global Health 

University of Maryland School of Medicine 

Baltimore, MD 

Term: 12/23/2020 – 6/30/2024 

DALEY, Matthew F, MD 

Senior Investigator 

Institute for Health Research, Kaiser Permanente Colorado 

Associate Professor of Pediatrics 

University of Colorado School of Medicine 

Aurora, CO 

Term: 1/4/2021 – 6/30/2024 

 

KOTTON, Camille Nelson, MD, FIDSA, FAST 

Clinical Director, Transplant and Immunocompromised Host Infectious Diseases 

Infectious Diseases Division, Massachusetts General Hospital 

Associate Professor of Medicine, Harvard Medical School 

Boston, MA 

Term: 12/23/2020 – 6/30/2024 
35

LOEHR, Jamie, MD, FAAFP

Owner, Cayuga Family Medicine

Ithaca, New York

Term: 7/26/2021 – 6/30/2025

LONG, Sarah S, MD 

Professor of Pediatrics 

Drexel University College of Medicine 

Section of Infectious Diseases 

St. Christopher’s Hospital for Children 

Philadelphia, Pennsylvania 

Term: 12/24/2020 – 6/30/2024 

MCNALLY, Veronica V, JD 

President and CEO Franny 

Strong Foundation 

West Bloomfield, Michigan 

Term: 10/31/2018 – 6/30/2022 

POEHLING, Katherine A, MD, MPH 

Professor of Pediatrics and Epidemiology and Prevention 

Director, Pediatric Population Health 

Department of Pediatrics 

Wake Forest School of Medicine 

Winston-Salem, NC 

Term: 7/1/2019 – 6/30/2023 

SÁNCHEZ, Pablo J, MD 

Professor of Pediatrics 

The Ohio State University – Nationwide Children’s Hospital 

Divisions of Neonatal-Perinatal Medicine and Pediatric Infectious Diseases 

Director, Clinical & Translational Research (Neonatology) 

Center for Perinatal Research 

The Research Institute at Nationwide Children's Hospital Columbus, Ohio 

Term: 7/1/2019 – 6/30/2023 

TALBOT, Helen Keipp, MD 

Associate Professor of Medicine 

Vanderbilt University 

Nashville, TN 

Term: 10/29/2018 – 6/30/2022 
36

EX OFFICIO MEMBERS 

 

Centers for Medicare and Medicaid Services (CMS) 

HANCE, Mary Beth 

Senior Policy Advisor 

Division of Quality, Evaluations and Health Outcomes 

Children and Adults Health Programs Group 

Center for Medicaid, CHIP and Survey & Certification Centers 

for Medicare and Medicaid Services 

Baltimore, MD 

Food and Drug Administration (FDA) 

FINK, Doran, MD, PhD 

Deputy Director, Clinical, Division of Vaccines and Related Products Applications 

Office of Vaccines Research and Review 

Center for Biologics Evaluation and Research 

Food and Drug Administration 

Silver Spring, MD 

 

Health Resources and Services Administration (HRSA) 

RUBIN, Mary, MD 

Chief Medical Officer 

Division of Injury Compensation Programs 

Rockville, MD 

Indian Health Service (IHS) 

CLARK, Matthew, MD, FAAP, FACP

Physician 

Chair, IHS National Pharmacy & Therapeutics Committee

Durango, CO

 

Office of Infectious Disease and HIV/AIDS Policy (OIDP)

KIM, David, MD, MA 

Director, Division of Vaccines, OIDP 

Office of the Assistant Secretary for Health 

Department of Health and Human Services 

Washington, DC 

 

National Institutes of Health (NIH) 

BEIGEL, John, MD 

Associate Director for Clinical Research 

Division of Microbiology and Infectious Diseases 

National Institute of Allergy and Infectious Diseases (NIAID) 

Bethesda, MD 
37

LIAISON REPRESENTATIVES 

American Academy of Family Physicians (AAFP)

ROCKWELL, Pamela G, DO 

Associate Professor, Department of Family Medicine, University of 

Michigan Medical School 

Medical Director, Dominos Farms Family Medicine 

Ann Arbor, MI 

 

American Academy of Pediatrics (AAP) 

MALDONADO, Yvonne, MD 

Senior Associate Dean for Faculty Development and Diversity 

Professor of Pediatrics and Health Research and Policy 

Chief, Division of Pediatric Infectious Diseases 

Stanford University School of Medicine 

Stanford, CA 

American Academy of Pediatrics (AAP) 

Red Book Editor

KIMBERLIN, David, MD 

Professor of Pediatrics 

Division of Pediatric Infectious Diseases 

The University of Alabama at Birmingham School of Medicine

Birmingham, AL 

 

American Academy of Physician Assistants (AAPA) 

LÉGER, Marie-Michèle, MPH, PA-C 

Senior Director, Clinical and Health Affairs 

American Academy of Physician Assistants 

Alexandria, VA 

American College Health Association (ACHA) 

CHAI, Thevy S., MD 

Director of Medical Services 

Campus Health Services 

University of North Carolina at Chapel Hill Chapel Hill, 

NC 

 

American College Health Association (ACHA) (alternate) 

MCMULLEN, Sharon, RN, MPH, FACHA 

Assistant Vice President of Student & Campus Life for Health and Wellbeing Cornell Health 

Ithaca, NY 

 

American College of Nurse Midwives (ACNM) 

HAYES, Carol E., CNM, MN, MPH 

Lead Clinician 

Clinical Quality Compliance and Management 

Planned Parenthood Southeast Atlanta, GA 

 
38

American College of Nurse Midwives (ACNM) (alternate) 

MEHARRY, Pamela M., PHD, CNM 

Midwifery Educator, Human Resources for Health 

In partnership with University of Rwanda and University of Illinois, Chicago 

American College of Obstetricians and Gynecologists (ACOG) 

ECKERT, Linda O, MD, FACOG 

Professor, Department of Obstetrics & Gynecology 

Adjunct Professor, Department of Global Health 

University of Washington 

Seattle, WA

American College of Physicians (ACP) 

GOLDMAN, Jason M, MD, FACP 

Affiliate Assistant Professor of Clinical Biomedical Science, Florida Atlantic University, Boca 

Raton, Florida 

Private Practice 

Coral Springs, FL 

American Geriatrics Society (AGS) 

SCHMADER, Kenneth, MD 

Professor of Medicine-Geriatrics Geriatrics 

Division Chief 

Duke University and Durham VA Medical Centers 

Durham, NC 

America’s Health Insurance Plans (AHIP) 

GLUCKMAN, Robert A, MD, MACP 

Chief Medical Officer, Providence Health Plans 

Beaverton, OR 

American Immunization Registry Association (AIRA) 

COYLE, Rebecca, MSEd 

Executive Director, AIRA

Washington, DC 

American Medical Association (AMA)

FRYHOFER, Sandra Adamson, MD 

Adjunct Associate Professor of Medicine Emory 

University School of Medicine 

Atlanta, GA 

American Nurses Association (ANA) 

RITTLE, Charles (Chad), DNP, MPH, RN Assistant 

Professor, Nursing Faculty 

Chatham University, School of Health Sciences 

Pittsburgh, PA 
39

American Osteopathic Association (AOA) 

GROGG, Stanley E, DO 

Associate Dean/Professor of Pediatrics 

Oklahoma State University-Center for Health Sciences 

Tulsa, OK 

American Pharmacists Association (APhA) 

HOGUE, Michael D., PharmD, FAPhA, FNAP

Dean and Professor of Loma Linda University School of Pharmacy

Director, Center for Interprofessional Education & Practice

Loma Linda, CA

Association of Immunization Managers (AIM) 

HOWELL, Molly, MPH 

Immunization Program Manager 

North Dakota Department of Health

Bismarck, ND 

Association for Prevention Teaching and Research (APTR) 

ZIMMERMAN, Richard, MD, MPH

Professor

University of Pittsburgh School of Medicine

Department of Family Medicine and Clinical Epidemiology

Pittsburgh, PA

Association of State and Territorial Health Officials (ASTHO) 

SHAH, Nirav D, MD, JD 

Director

Maine Center for Disease Control and Prevention

Augusta, ME 

Biotechnology Industry Organization (BIO) 

ARTHUR, Phyllis A, MBA 

Senior Director, Vaccines, Immunotherapeutics and Diagnostics Policy 

Washington, DC 

Council of State and Territorial Epidemiologists (CSTE) 

HAHN, Christine, MD 

State Epidemiologist 

Office of Epidemiology, Food Protection and Immunization Idaho 

Department of Health and Welfare 

Boise, ID 

Council of State and Territorial Epidemiologists (CSTE) (alternate) 

LETT, Susan, MD, MPH 

Medical Director, Immunization Program 

Division of Epidemiology and Immunization 

Massachusetts Department of Public Health 

Boston, MA 
40

Canadian National Advisory Committee on Immunization (NACI) 

DEEKS, Shelley, MD, MHSc, FRCPC, FAFPHM

Deputy Chief Medical Officer of Health, Department of Health and Wellness, Nova Scotia

Associate Professor, Dalla Lana School of Public Health, University of Toronto

Chair, National Advisory Committee on Immunization

Halifax, Nova Scotia

Infectious Diseases Society of America (IDSA) 

BAKER, Carol J., MD 

Professor of Pediatrics 

Molecular Virology and Microbiology 

Baylor College of Medicine 

Houston, TX 

International Society for Travel Medicine (ISTM) 

BARNETT, Elizabeth D, MD Professor of 

Pediatrics 

Boston University School of Medicine 

Boston, MA 

National Association of County and City Health Officials (NACCHO)

ZAHN, Matthew, MD 

Medical Director, Epidemiology 

Orange County Health Care Agency 

Santa Ana, CA 

National Association of County and City Health Officials (NACCHO) (alternate)

DUCHIN, Jeffrey, MD 

Health Officer and Chief, Communicable Disease

Epidemiology and Immunization Section 

Public Health - Seattle and King County 

Professor in Medicine 

Division of Allergy and Infectious Diseases 

University of Washington School of Medicine and School of Public Health

Seattle, WA 

National Association of Pediatric Nurse Practitioners (NAPNAP) 

STINCHFIELD, Patricia A, RN, MS, CPNP 

Director 

Infectious Disease/Immunology/Infection Control

Children's Hospitals and Clinics of Minnesota 

St. Paul, MN 

National Foundation for Infectious Diseases (NFID) 

SCHAFFNER, William, MD 

Chairman, Department of Preventive Medicine 

Vanderbilt University School of Medicine 

Nashville, TN 
41

National Foundation for Infectious Diseases (NFID) (alternate)

DALTON, Marla, PE, CAE 

Executive Director & CEO 

National Foundation for Infectious Diseases (NFID) 

Bethesda, MD 

National Medical Association (NMA) 

WHITLEY-WILLIAMS, Patricia, MD Professor and Chair 

University of Medicine and Dentistry of New Jersey Robert Wood 

Johnson Medical School 

New Brunswick, NJ 

Pediatric Infectious Diseases Society (PIDS) 

O’LEARY, Sean, MD, MPH 

Associate Professor of Pediatrics 

Pediatric Infectious Diseases 

General Academic Pediatrics 

Children’s Hospital Colorado 

University of Colorado School of Medicine 

Pediatric Infectious Diseases Society (PIDS) (alternate)

SAWYER, Mark H, MD 

Professor of Clinical Pediatrics 

University of California, San Diego School of Medicine 

San Diego, CA 

Pharmaceutical Research and Manufacturers of America (PhRMA) 

ROBERTSON, Corey, MD, MPH 

Senior Director, US Medical, Sanofi Pasteur 

Swiftwater, PA 

Society for Adolescent Health and Medicine (SAHM) 

MIDDLEMAN, Amy B, MD, MSEd, MPH 

Professor of Pediatrics 

Chief, Section of Adolescent Medicine 

University of Oklahoma Health Sciences Center

Oklahoma City, OK 

Society for Healthcare Epidemiology of America (SHEA)

DREES, Marci, MD, MS 

Chief Infection Prevention Officer & Hospital Epidemiologist 

ChristianaCare 

Wilmington, DE 

Associate Professor of Medicine 

Sidney Kimmel Medical College at Thomas Jefferson University Philadelphia, PA
42

ACRONYMS USED IN THIS DOCUMENT 

Acronym Extension

AAFP American Academy of Family Physicians 

AAP American Academy of Pediatrics

ACHA American College Health Association 

ACIP Advisory Committee on Immunization Practices

ACOG American College of Obstetricians and Gynecologists

ACP American College of Physicians 

AE Adverse Event

AHIP America’s Health Insurance Plans

AI/AN American Indian/Alaskan Native 

AIM Association of Immunization Managers 

AIRA American Immunization Registry Association 

AMA American Medical Association

AOA American Osteopathic Association 

APhA American Pharmacists Association 

AR Adverse Reaction 

ARI Acute Respiratory Illness 

ASTHO Association of State and Territorial Health Officers 

BEST Biologics Effectiveness and Safety System

BLA Biologics License Application 

CBO Community-Based Organizations 

CDC Centers for Disease Control and Prevention

CHIP Children’s Health Insurance Program 

CISA Clinical Immunization Safety Assessment 

CMS Center for Medicare and Medicaid Services

COI Conflict of Interest 

CSTE Council of State and Territorial Epidemiologists 

DFO Designated Federal Official

DoD Department of Defense

DSMB Data Safety Monitoring Board 

DUA Data Use Agreement 

DVA Department of Veterans Affairs

ED Emergency Department

EHR Electronic Health Record 

ET Eastern Time

EtR Evidence to Recommendation 

EUA Emergency Use Authorization 

FDA Food and Drug Administration

FQHC Federally Qualified Health Center 

GBS Guillain-Barré Syndrome 

GMR Geometric Mean Ratio 

GMT Geometric Mean Titers 

GRADE Grading of Recommendation Assessment, Development and Evaluation 

HCP Healthcare Personnel / Providers

HHS (Department of) Health and Human Services
43

IDSA Infectious Disease Society of America 

IHS Indian Health Service 

IIS Immunization Information System 

MMWR Morbidity and Mortality Weekly Report

NACCHO National Association of County and City Health Officials 

NACI National Advisory Committee on Immunization Canada

NAPNAP National Association of Pediatric Nurse Practitioners 

NCEZID National Center for Emerging and Zoonotic Infectious Diseases 

NCHS National Center of Health Statistics 

NCIRD National Center for Immunization and Respiratory Diseases 

NFID National Foundation for Infectious Diseases 

NIAID National Institute of Allergy and Infectious Diseases

NIH National Institutes of Health

NMA National Medical Association 

NP Nasopharyngeal

NVAC National Vaccine Advisory Committee 

NVPO National Vaccine Program Office 

NVSN New Vaccine Surveillance Network 

OIDP Office of Infectious Disease and HIV/AIDS Policy

PCP Primary Care Provider/Practitioner

PCR Polymerase Chain Reaction

PHAC Public Health Agency Canada 

PHE Public Health Emergency 

PICO Population, Intervention, Comparison, Outcomes

PIDS Pediatric Infectious Disease Society 

RCA Rapid Cycle Analysis 

RCT Randomized Controlled Trial

SAE Serious Adverse Event 

SAHM Society for Adolescent Health and Medicine 

SHEA Society for Healthcare Epidemiology of America 

SME Subject Matter Expert

SVI Social Vulnerability Index 

UK United Kingdom

US United States

USG United States Government

VAERS Vaccine Adverse Event Reporting System

VE Vaccine Efficacy

VE Vaccine Effectiveness

VFA Vaccines for Adults 

VFC Vaccines For Children 

VRBPAC Vaccines and Related Biological Products Advisory Committee 

VSD Vaccine Safety Datalink

WG Work Group

WHO World Health Organization