Weekly COVID-19 cases among persons ≥5 years old among unvaccinated and vaccinated with a BNT162b2 [Pfizer-BioNTech] primary series by age group — 22 U.S. jurisdictions, January 16 to May 28, 2022
Reported numbers of SARS-CoV-2 infections by age group [5–11, 12–17, 18–49, 50–64, ≥65 years of age] from 22 U.S. jurisdictions [AR, AZ, CA, CO, CT, DC, FL, GA, IN, KS, MI, MA, MN, NC, NE, NJ, NM, NYC, PHL, TN, UT, WI ]; ~53% of the U.S. population] with routine linkages between COVID-19 case surveillance and immunization information system [IIS] data reported to CDC during January 16, 2022 – May 28, 2022.
Vaccine administration [coverage] data reported to CDC were aggregated by U.S. reporting jurisdiction, MMWR week of vaccination [≥14 days after completing the primary vaccine series], FDA-approved vaccine products, and age group [5–11, 12–17, 18–49, 50–64, ≥65 years].
Vaccination status: A person vaccinated with at least a primary series had SARS-CoV-2 RNA or antigen detected on a respiratory specimen collected ≥14 days after verifiably completing BNT162b2 [Pfizer-BioNTech] primary series. An unvaccinated person had SARS-CoV-2 RNA or antigen detected on a respiratory specimen and has not been verified to have received COVID-19 vaccine. Excluded were partially vaccinated people who received at least one FDA-authorized vaccine dose but did not complete a primary series ≥14 days before collection of a specimen where SARS-CoV-2 RNA or antigen was detected.
To estimate the number of unvaccinated persons in each MMWR week, the 2019 U.S. Census population estimates by jurisdiction and age group were used [except for California, where State Department of Finance 2021 population projections were determined to be more accurate]. The number of unvaccinated persons each MMWR week was estimated by subtracting the cumulative number of vaccinated [all products] and partially vaccinated persons [all products] from the respective population totals for each jurisdiction and age group.
Continuity correction: A continuity correction has been applied to the denominators by capping the percent population coverage at 95%. To do this, we assumed that at least 5% of each age group would always be unvaccinated in each jurisdiction. Adding this correction ensures that there is always a reasonable denominator for the unvaccinated population that would prevent rates from growing unrealistically large due to potential overestimates of vaccination coverage.