U.S. Food & Drug Administration

10903 New Hampshire Avenue

Silver Spring, MD 20993

w ww.fda.gov

March 10, 2023 

Joseph A. Ladapo, M.D., Ph.D. 

State Surgeon General

Florida Department of Health 

4052 Bald Cypress Way, Bin A-00 

Tallahassee, FL 32399-1701 

Sent Via Electronic Mail Only

Dear Dr. Ladapo,

Thank you for your letter regarding COVID-19 vaccine safety. We appreciate this opportunity to 

address your questions and we would like to correct the associated misinterpretations and 

misinformation about the data from the Vaccine Adverse Event Reporting System (VAERS), in 

the spirit of transparency and supporting and serving the health of our nation. 

The U.S. Food and Drug Administration (FDA) and the Centers for Disease Control and 

Prevention (CDC) continue to diligently monitor a variety of data sources to identify any 

potential risks of the vaccines and to ensure that information is available to the public. That said, 

focusing on adverse events in the absence of causal association and without the perspective of 

countervailing benefits is a great disservice to both individuals and public health. Like every 

other medical intervention, there are adverse effects from vaccination. Serious adverse events 

from COVID-19 vaccines are rare and are far outweighed by the benefits of these vaccines for 

every age group. 

The claim that the increase of VAERS reports of life-threatening conditions reported from 

Florida and elsewhere represents an increase of risk caused by the COVID-19 vaccines is 

incorrect, misleading and could be harmful to the American public. The FDA-approved and 

FDA-authorized COVID-19 vaccines have met FDA’s rigorous scientific and regulatory 

standards for safety and effectiveness and these vaccines continue to be recommended for use by 

CDC for all people six months of age and older. Both FDA and CDC have continued to collect 

outcome data from multiple sources that demonstrate the clear benefit of COVID-19 vaccines in 

preventing death, serious illness, and hospitalization from SARS-CoV-2 infection, along with

indicating a modest benefit in the prevention of infection and transmission that wanes over time, 

even as new variants have emerged. Additional benefits include a reduced risk of known 

complications from SARS-CoV-2 infection, including post-COVID conditions, COVID-19-

associated stroke and heart disease, and COVID-19-induced venous thromboembolism.
Dr. Joseph A. Ladapo 

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U.S. Food & Drug Administration

10903 New Hampshire Avenue

Silver Spring, MD 20993

w ww.fda.gov

Centers for Disease Control and Prevention

Atlanta, GA 30329-4027

www.cdc.gov

Reports of adverse events to VAERS following vaccination do not mean that a vaccine 

caused the event. Since December 2020, almost 270 million people have received more than 

670 million doses of COVID-19 vaccines in the U.S., with over 50 million people having 

received the updated bivalent vaccine. The Emergency Use Authorizations (EUAs) for the 

COVID-19 Vaccines require sponsors and vaccine providers to report certain adverse 

events through VAERS, so more reports should be expected. Recent concerns about 

increased reports of cardiovascular events provide an instructive example of the need to do 

further analysis when increased reporting of an event occurs. Despite increased reports of these 

events, when the concern was examined in detail by cardiovascular experts, the risk of stroke and 

heart attack was actually lower in people who had been vaccinated, not higher. 

FDA and CDC physicians continuously screen and analyze VAERS data for possible safety 

concerns related to the COVID-19 vaccines. For signals identified in VAERS, physicians from 

FDA and CDC screen individual reports, inclusive of comprehensive medical record review. 

Most reports do not represent adverse events caused by the vaccine and instead represent a preexisting condition that preceded vaccination or an underlying medical condition that precipitated 

the event. 

Adverse events must be compared to background rates in the population. This VAERS 

review methodology allows for successful identification of rare adverse reactions related to 

specific COVID-19 vaccines (e.g., Guillain-Barré Syndrome, thrombosis with thrombocytopenia 

syndrome , and immune thrombocytopenia following use of the Janssen COVID-19 Vaccine or 

myocarditis, pericarditis and anaphylaxis following use of the Pfizer-BioNTech and Moderna 

COVID-19 vaccines). Information about these adverse reactions is included in the fact sheets for 

healthcare providers administering vaccine and vaccine recipients and caregivers. FDA and CDC 

also continue to post summaries of the key safety monitoring findings and present the data 

publicly at regularly scheduled advisory committee meetings. 

In addition to VAERS, FDA and CDC utilize complementary active surveillance systems to 

monitor the safety of COVID-19 vaccines. Active surveillance involves proactively obtaining 

and rapidly analyzing information occurring in millions of individuals recorded in large 

healthcare data systems to verify safety signals identified through passive surveillance or to 

detect additional safety signals that may not have been reported as adverse events to passive 

surveillance systems. FDA is conducting active surveillance using the Sentinel BEST (Biologics 

Effectiveness and Safety) System and collaborating with the Center for Medicare and Medicaid 

Services (CMS) and Department of Veterans Affairs (VA). These efforts complement those of 

CDC’s Vaccine Safety Datalink (VSD) and the v-safe text-based monitoring system for 

conducting surveillance of adverse events, as well as the Clinical Immunization Safety 

Assessment (CISA) Project. FDA and CDC are also collaborating with other non-federal 

partners, including state and local health departments. 

Based on available information for the COVID-19 vaccines that are authorized or 

approved in the United States, the known and potential benefits of these vaccines clearly 

outweigh their known and potential risks. Additionally, not only is there no evidence of 

increased risk of death following mRNA vaccines, but available data have shown quite the 
Dr. Joseph A. Ladapo 

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U.S. Food & Drug Administration

10903 New Hampshire Avenue

Silver Spring, MD 20993

w ww.fda.gov

Centers for Disease Control and Prevention

Atlanta, GA 30329-4027

www.cdc.gov

opposite: that being up to date on vaccinations saves lives compared to individuals who did 

not get vaccinated. Multiple well conducted, peer-reviewed, published studies here and here

demonstrate that the risk of death, serious illness and hospitalization is higher for unvaccinated 

individuals for every age group. Because we are not the only country in the world using COVID19 vaccines, we also benefit from the experience of other countries. More than 13 billion doses 

of COVID-19 vaccines have been given around the world, including hundreds of millions of 

doses of mRNA vaccines and hundreds of millions of doses to children. Consistent with our data, 

these multiple international partners have robust monitoring for both safety and effectiveness. 

They find little evidence of widespread adverse events, also detect rare events as we do, and 

conclude that the benefits of the vaccines generally far outstrip their risks. 

While many studies could be cited, a retrospective cohort study using the CDC’s Vaccine Safety 

Datalink found no increased risk of death for the mRNA and Janssen vaccines across age, sex, 

and race/ethnicity groups. They found that crude non-COVID-19 mortality rates among COVID19 vaccine recipients were lower than those among unvaccinated comparators. Another study

using mathematical modeling estimated that the vaccines saved an estimated 14 million lives 

from COVID-19 in 185 countries and territories between December 8, 2020, and December 8, 

2021. Vaccination is also associated with a reduction of post-acute sequelae of COVID-19. The 

data supporting the benefits of the COVID-19 vaccines have been critically reviewed and 

accepted by the medical and public health community, including state and local public health 

agencies and academic and professional organizations. 

The most recent estimate is that those who are up to date on their vaccination status have a 

9.8 fold lower risk of dying from COVID-19 than those who are unvaccinated and 2.4 fold 

lower risk of dying from Covid-19 than those who were vaccinated but had not received the 

updated, bivalent vaccine. Roughly 90% of deaths from COVID-19, as carefully classified by 

the CDC, in recent months have occurred among those who were not up to date on their 

vaccines. Furthermore, as stated above, emerging reports indicate a possible reduction in the risk 

of post-COVID conditions in vaccinated people who survive an infection. 

As the leading public health official in state, you are likely aware that seniors in Florida are 

under-vaccinated, with just 29% of seniors having received an updated bivalent vaccine, 

compared to the national average of 41% coverage in seniors. It is the job of public health 

officials around the country to protect the lives of the populations they serve, particularly 

the vulnerable. Fueling vaccine hesitancy undermines this effort.

We agree that communication between patients and their health care providers is critical, and 

fully support clear, accurate communication about the benefits and risks of medical products. It 

is inaccurate to suggest that the federal government will “retaliate” against any health care 

provider for communicating with their patients about the benefits and risks of a particular 

medical product. 

Over the course of the pandemic, FDA and CDC have held numerous public meetings to discuss 

the safety and effectiveness of the COVID-19 vaccines where detailed safety data are shared 

with outside experts and public comment is encouraged. Further, FDA publishes the full 
Dr. Joseph A. Ladapo 

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U.S. Food & Drug Administration

10903 New Hampshire Avenue

Silver Spring, MD 20993

w ww.fda.gov

Centers for Disease Control and Prevention

Atlanta, GA 30329-4027

www.cdc.gov

regulatory action package containing hundreds of pages summarizing clinical studies and review 

for each COVID-19 approval on FDA’s website (see “COVID-19 Vaccines Authorized for 

Emergency Use or FDA Approved”) and CDC publishes an extensive amount of information on 

their clinical use in Interim Clinical Considerations. Complete information about both benefits 

and risks helps health care providers better care for their patients. 

Unfortunately, the misinformation about COVID-19 vaccine safety has caused some 

Americans to avoid getting the vaccines they need to be up to date. This has led to 

unnecessary death, severe illness and hospitalization. These tragic outcomes not only have a 

devastating effect on individuals and their families, but they also create a tremendous strain on 

our healthcare systems and clinicians, potentially compromising care for other patients. 

We stand firmly behind the safety and effectiveness of the mRNA COVID-19 vaccines, which 

are fully supported by the available scientific data. Staying up to date on vaccination is the best 

way to reduce the risks of death and serious illness or hospitalization from COVID-19. 

Misleading people by overstating the risks, or emphasizing the risks without acknowledging the 

overwhelming benefits, unnecessarily causes vaccine hesitation and puts people at risk of death 

or serious illness that could have been prevented by timely vaccination. 

Sincerely,

 

Robert M. Califf, MD Rochelle P. Walensky, MD, MPH 

Commissioner Director 

U.S. Food and Drug Administration Centers for Disease Control and Prevention