Evidence on trends in uptake of childhood vaccines and association with COVID-19 vaccination rates.

IMPORTANCE

Childhood vaccination rates have declined in recent years; there is also concern that resistance to COVID-19 vaccines could spill over to childhood vaccines.

OBJECTIVES

To use local-level data to study trends in childhood vaccination rates and heterogeneity in local rates; including how many areas are below herd-immunity thresholds, and assess the association between COVID-19 vaccine hesitancy and childhood vaccination.

DESIGN

We report, for 11 states with available data, vaccination rates for measles, mumps, rubella (MMR), and diphtheria, tetanus, acellular pertussis (DTaP) vaccines, including percentage of schools/counties with rates ≥95 %, 90-95 %, 80-90 %, and < 80 %. We also study the association between county-level COVID-19 vaccination rates and change from 2019 to 2022 in MMR and DTaP vaccination rates.

EXPOSURE: School/county level vaccination rates; county-level COVID-19 vaccine hesitancy, proxied by the percent of the adult population in each county that did not complete primary COVID-19 vaccination.

MAIN OUTCOMES: Percentage of school/counties with MMR/DTaP vaccination rates within specified ranges, mean vaccination rates, and change in MMR/DTaP vaccination rates between 2019 and 2022.

RESULTS

On average, childhood vaccination rates declined from 2019 to 2022 in states that allow non-medical exemptions, but with substantial heterogeneity within and across states. The largest declines were in already low-vaccination schools. COVID-19 vaccine hesitancy was associated with a somewhat larger 2019-to-2022 decline in childhood vaccination rates in rural counties and strongly Republican-leaning counties.

CONCLUSION

Vaccination rates fell from 2019 to 2022, continuing a longer trend toward lower rates. For measles and pertussis, childhood vaccination rates are below herd-immunity levels in many local communities, sometimes substantially so. We used two proxies for potential spillover of COVID-19 vaccine hesitancy to childhood vaccines (rural indicator and Republican-leaning indicator); these proxies can explain a modest part of the decline childhood vaccination in rural and Republican-leaning counties, but most of the explanation lies elsewhere.