Vaccine coverage for children declined by the age of 2 for eight vaccines, the Centers for Disease Control and Prevention said in a new study.
CDC researchers compared the percentage of children vaccinated with recommended shots across two time periods. The first set of children was born in 2019 and 2020. The second set was born in 2021 and 2022.
The sharpest declines were for vaccines against influenza, with a decrease of 7.4 percent, to 53.5 percent; rotavirus, with a decrease of 1.7 percent, to 74.2 percent; and pneumococcal disease, with a decrease of 1.5 percent, to 80.5 percent. Influenza vaccine coverage has plummeted in recent years and has been down 12 percent since 2019.
Coverage was also lower for vaccines against hepatitis A, hepatitis B, chickenpox, Haemophilus influenzae type b, and polio, the CDC said, although the declines were slight for polio and the full three-dose hepatitis B vaccine series.
About the same percentage of children had received the measles, mumps, rubella vaccine, and several doses of the diphtheria, tetanus, pertussis vaccine by the age of 2 in the cohorts, according to the study. The percentage of children who had received no vaccines, 1.2 percent, was unchanged.
The newly published research was based on the CDC’s National Immunization Survey, which monitors vaccination uptake among children and adults.
CDC researchers in the survey collection call households with children aged 19 to 35 months and ask questions to caregivers, usually parents. If caregivers provide consent, then doctors are contacted to provide information on which vaccines the children have received. Researchers use the answers and data to form estimates of vaccine coverage.
In 2024, 23 percent of households responded to interview requests. Data was provided by about half of the health care providers for children whose caregivers completed interviews.
The population ended up being 27,392 children, including 1,355 in Texas, 1,027 in Pennsylvania, and 1,000 in New York. Children were included from all 50 states, the District of Columbia, and the territories of Guam and Puerto Rico.
“Maintaining high levels of vaccination and improving coverage among groups and in areas in which rates have declined could help protect children from vaccine-preventable morbidity and mortality,” Holly Hill, a medical officer at the CDC’s Immunization Services Division, and co-authors wrote in the paper.
Limitations included researchers relying on cell phones, which omitted households without them. Authors declared no conflicts of interest.