Effectiveness of BNT162b2 Vaccine against Critical Covid-19 in Adolescents

摘要

Background:The increasing incidence of pediatric hospitalizations associated with coronavirus disease 2019(Covid-19)caused by the B.1.617.2(delta)variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)in the United States has offered an opportunity to assess the real-world effectiveness of the BNT162b2 messenger RNA vaccine in adolescents between 12 and 18 years of age.Methods:We used a case-control,test-negative design to assess vaccine effectiveness against Covid-19 resulting in hospitalization,admission to an intensive care unit(ICU),the use of life-supporting interventions(mechanical ventilation,vasopressors,and extracorporeal membrane oxygenation),or death.Between July 1 and October 25,2021,we screened admission logs for eligible case patients with laboratory-confirmed Covid-19 at 31 hospitals in 23 states.We estimated vaccine effectiveness by comparing the odds of antecedent full vaccination(two doses of BNT162b2)in case patients as compared with two hospitalbased control groups:patients who had Covid-19-like symptoms but negative results on testing for SARS-CoV-2(test-negative)and patients who did not have Covid-19-like symptoms(syndrome-negative).