COVID-19 Vaccination and Incidence of Pediatric SARS-CoV-2 Infection and Hospitalization (2024)
We provide evidence that California’s pediatric COVID-19 immunization program averted 376 085 (95% PI, 348 355-417 328) reported cases and 273 (95% PI, 77-605) hospitalizations among children aged 6 months to 15 years during the 4 to 7 months following vaccine availability. This represents a reduction of 26.3% of the number of cases that would have been seen in this population absent the vaccine.
The cumulative effect of vaccination at the population level may be meaningful even if individual vaccine effectiveness is low. While influenza vaccine effectiveness was estimated at 29% in 2017-2018,28 it was estimated that widespread vaccination averted more than 3.1 million cases of influenza in the US.
COVID-19-associated hospitalization were approximately 10.5 times higher in unvaccinated adults compared with adults vaccinated with a primary series and a booster dose during January to April 2022, when the Omicron variant was predominant. This suggests that COVID-19 vaccines continue to effectively prevent hospitalizations in all adults.
