COVID-19 Vaccine Safety Technical (VaST) 

Work Group 

Safety assessment of booster doses 

H. Keipp Talbot, MD MPH (VaST Chair)

Robert H. Hopkins, Jr., MD (NVAC Chair)

Advisory Committee on Immunization Practices

April 20, 2022
COVID-19 Vaccine Safety Technical (VaST) Work Group

Objectives

 Review, evaluate, and interpret post-authorization/approval COVID-19 

vaccination safety data

 Serve as the central hub for technical subject matter expertise from federal 

agencies conducting post-authorization/approval safety monitoring

 Advise on analyses, interpretation, and presentation of vaccine safety data

 Provide updates to the ACIP COVID-19 Vaccines Work Group and the entire 

ACIP on COVID-19 vaccine safety

VaST meetings 

 December 21, 2020 – present: 55 meetings to review vaccine safety data

2
start 

of vax

safety monitoring timeline

active surveillance, passive 

surveillance, case consults

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VaST review & assessment of booster dose safety data

VaST reviews Assessment presented to ACIP

September 13, 2021 – v-safe and Israeli data September 22, 2021

October 18, 2021 – v-safe and VAERS October 21, 2021

November 8, 2021 – v-safe and VAERS November 19, 2021

December 6, 2021 – v-safe and VAERS

January 4, 2022 (12–15-year-olds) December 13, 2021 – Israeli data

March 28, 2022 – VSD and VAERS

April 11, 2022 – Department of Veteran’s Affairs April 20, 2022

April 18, 2022 – VSD, VAERS, v-safe

VAERS, Vaccine Adverse Event Reporting System; VSD, Vaccine Safety Data Link
Safety of first mRNA COVID-19 booster dose

 v-safe

 Age ≥18 years: injection site, systemic reactions less frequent following 

booster than following primary dose 2

 Age 12–17 years: frequency of reactions equal or slightly higher following 

booster than following primary dose 2

 Vaccine Adverse Event Reporting System (VAERS)

 Myocarditis rates highest among males ages 12–29 years

• Rates higher than background, lower than after primary dose 2

 Pericarditis reported similarly by sex and age group

• Low case counts complicate estimation of rates

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Safety of first mRNA COVID-19 booster dose (continued)

 Vaccine Safety Datalink (VSD) rapid cycle analysis

 Only safety signal: myocarditis/pericarditis in the 21 days after a 1st booster dose

 Myocarditis/pericarditis differed by age group

• 12–39 years: mostly myocarditis/myopericarditis, onset < 7 days after 

vaccination; rate per million 1st booster doses not higher than after primary 

series dose 2 

• ≥ 40 years: mostly pericarditis, onset up to 3 weeks after vaccination

 Department of Veteran’s Affairs (VA) rapid cycle analysis

 No safety signals observed for mRNA booster dose in a 21-day window. 

 Chart review confirmed 15 of 40 myocarditis/pericarditis reports after booster dose

• 10 pericarditis, 5 myocarditis

• 14 of 15 in persons age ≥ 40 years

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VaST assessment

COVID-19 vaccine first booster dose safety data to inform 

second dose booster vaccination

 VaST has provided assessments on booster dose safety at 4 ACIP meetings

 Today’s assessment included data from VSD as well as v-safe, VAERS, VA 

 Reactogenicity is similar to or lower than that seen after the primary series

 Myocarditis risk appears lower than after a primary series dose 2

 Further work and analyses are needed to understand pericarditis risk

 While data do not suggest safety concerns beyond those previously 

identified, VaST will carefully monitor data on myocarditis and pericarditis 

after booster doses

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 VaST will continue to 

• Review further safety regarding booster doses as data become available

• Collaborate with global vaccine safety colleagues on key issues

• Provide updates to the ACIP Work Group and ACIP at future meetings

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VaST plans

COVID-19 vaccine booster dose safety data
VaST Members

VaST Members

Keipp Talbot (ACIP)

Robert Hopkins (NVAC)

Matt Daley

Grace Lee

Veronica McNally

Kathy Edwards

Lisa Jackson

Jennifer Nelson

Laura Riley

Robert Schechter

Patricia Whitley-Williams

CDC Co-Leads

Lauri Markowitz

Melinda Wharton

Ex Officio and Liaison Representatives 

Tatiana Beresnev (NIH)

Karen Farizo; Hui Lee Wong (FDA)

Valerie Marshall (OIDP)

Jeffrey Kelman (CMS)

Matthew Clark (IHS)

Mary Rubin (HRSA)

Fran Cunningham (VA)

Limone Collins (DoD)

Administrative Support

Jared Woo

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