COVID-19 vaccine moderately effective (48%) at preventing symptomatic infection in children 5 to 11 years old

Référence

Cohen-Stavi CJ, Magen O, Barda N, et al. BNT162b2 vaccine effectiveness against omicron in children 5 to 11 years of age. N Engl J Med 2022;387(3):227-236.

Sommaire

Although hospitalization and death are rare sequelae of COVID-19 infection in children, it is important to remember that while the flu typically kills 50 to 150 children per year in the United States, COVID-19 caused more than 600 pediatric deaths (and numerous hospitalizations) in 2021. This study from Israel is a population-based observational study in which researchers matched 94,728 children vaccinated after November 23, 2021, with the same number of otherwise similar unvaccinated children, and then looked at the number of infections in each group through January 7, 2022. A further 15,280 in the unvaccinated got vaccinated during the study period and were rematched as now being members of the vaccinated group. Matching was on the basis of age, sex, population sector (Jewish, Arab, or ultra-Orthodox Jewish), residence, weight, and number of comorbidities. Children received 2 doses of the Pfizer-BioNTech vaccine, and effectiveness overall was 48% at 7 to 21 days after the second dose. Effectiveness was greater for younger children: 69% for ages 5 to 6 years, 49% for ages 7 to 9 years, and 36% for ages 10 to 11 years. Effectiveness after the first dose was only 18%. There were only 3 hospitalizations (2 in the unvaccinated group and 1 in the vaccinated group). The study was supported by the European Union, the United Kingdom's Medical Research Council, and the Morris-Singer Fund.