A 7 year-old child holds a sticker she received after getting the Pfizer-BioNTech Covid-19 vaccine ... [+]
A new California-based study including the data of 3.9 million pediatric Covid-19 cases found that thanks to the state’s Covid-19 immunization program, there was a reduction of 26.3% in the number of cases among children aged 6 months to 15 years.
More specifically, the researchers estimated that there was a 37.1% reduction in Covid-19 cases among adolescents aged 12 to 15 years and a 23.7% reduction among children aged 5 to 11 years. Whereas Covid-19 vaccinations were associated with 24.4% fewer hospitalizations among children aged 6 months to 4.9 years.
“Despite low vaccination coverage, pediatric COVID-19 immunization in California averted 376,085 reported cases and 273 hospitalizations among children aged 6 months to 15 years over approximately 4 to 7 months following vaccination availability,” the researchers wrote in their study that was published in JAMA Network Open on April 23, 2024.
“COVID-19 vaccines are safe for children. However, concerns over vaccine-related adverse events, lower vaccine effectiveness against illness in children, and perceptions of a milder disease course in children have resulted in high rates of parental vaccine hesitancy and resistance to pediatric vaccine mandates,” the authors added. “While California has among the highest rates of vaccination in the US, pediatric vaccination coverage lags that of adults substantially, with only 8.2% of children younger than 5 years and 37.8% of children aged 5 to 11 years fully vaccinated as of May 2023. Severe manifestations of COVID-19 are rare among children, but can occur.”
Lead author Justin V. Remais of the University of California, Berkeley, and colleagues, analyzed data on 3,913,063 pediatric Covid-19 cases and 12,740 hospitalizations in California. They then studied how pediatric Covid-19 vaccinations were introduced to children belonging to different age groups and calculated statewide outcomes that could be associated with vaccinations preventing or reducing new pediatric cases and Covid-19-related hospitalizations between April 2020 and February 2023. The team obtained data from the California COVID-19 Reporting System.
Of the 3.9 million pediatric Covid-19 cases reported in California among children younger than 18 years, 1.2% cases were among infants younger than 6 months, 13.2% in children aged 6 to 4.9 years, and 38.6% in children aged 12 to 15 years. The highest percentage of cases (40.7%) was in children aged 5 to 11 years. Among pediatric Covid-19 hospitalized cases, adolescents aged 12 to 15 were the most hospitalized group (30.8%).
"On average, every increase of 10 vaccinations per 1000 children corresponded to a reduction of 0.9 cases per 1000 children for individuals aged 6 to 59 months, 3.5 cases per 1000 children for those aged 5 and 11 years, and 2 cases per 1000 children for adolescents aged 12 to 15 years," the researchers explained.
"Prior work has similarly reported a high impact of widespread administration of mRNA vaccines in adult populations. In California, COVID-19 vaccines were estimated to avert more than 1.5 million cases, 72,000 hospitalizations, and 19,000 deaths statewide during the first 10 months of vaccination (through October 16, 2021). In the US, each 10% increase in vaccination coverage among individuals aged 18 years or older at the county level was associated with an 8% reduction in mortality and a 7% reduction in incidence," the researchers added.
