On November 19, the Centers for Disease Control and Prevention (CDC) strengthened its guidance to recommend a booster shot https://www.cdc.gov/vaccines/covid-19/clinical-considerations/covid-19-vaccines-us.html#considerations-covid19-vax-booster of the Pfizer-BioNTech or Moderna vaccines for all adults ages 18 years or older who completed their primary vaccination more than six months ago. See the CDC statement https://www.cdc.gov/media/releases/2021/s1119-booster-shots.html This recommendation aligns with and follows the Federal Drug Administration’s authorization of the Pfizer-BioNTech and Moderna vaccines as a booster and supplements previous guidance on boosters for other COVID-19 vaccines, covered in this bulletin https://content.govdelivery.com/accounts/USHHSHRSA/bulletins/2f91b54 The following resources are available to help health centers understand what this means: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/booster-shot.html and https://www.cdc.gov/vaccines/covid-19/clinical-considerations/covid-19-vaccines-us.html