Effectiveness of COVID-19 Pfizer-BioNTech BNT162b2 mRNA Vaccination in Preventing COVID-19–Associated Emergency Department and Urgent Care Encounters and Hospitalizations Among Nonimmunocompromised Children and Adolescents Aged 5–17 Years — VISION Network, 10 States, April 2021–January 2022
Authors: Nicola P. Klein, Melissa S. Stockwell, Maria Demarco, Manjusha Gaglani, Anupam B. Kharbanda, Stephanie A. Irving, Suchitra Rao, Shaun J. Grannis, Kristin Dascomb, Kempapura Murthy, Elizabeth A. Rowley, Alexandra F. Dalton, Malini B. DeSilva, Brian E. Dixon, Karthik Natarajan, Edward Stenehjem, Allison L. Naleway, Ned Lewis, Toan C. Ong, Palak Patel, Deepika Konatham, Peter J. Embi, Sarah E. Reese, Jungmi Han, Nancy Grisel, Kristin Goddard, Michelle A. Barron, Monica Dickerson, I-Chia Liao, William F. Fadel, Duck-Hye Yang, Julie Arndorfer, Bruce Fireman, Eric P. Griggs, Nimish R. Valvi, Carly Hallowell, Ousseny Zerbo, Sue Reynolds, Jill Ferdinands, Mehiret H. Wondimu, Jeremiah Williams, Catherine H. Bozio, Ruth Link-Gelles, Eduardo Azziz-Baumgartner, Stephanie J. Schrag, Mark G. Thompson, Jennifer R. Verani
Journal: MMWR Morbidity and Mortality Weekly Report (2022)

The efficacy of the BNT162b2 (Pfizer-BioNTech) vaccine against laboratory-confirmed COVID-19 exceeded 90% in clinical trials that included children and adolescents aged 5-11, 12-15, and 16-17 years (1-3). Limited real-world data on 2-dose mRNA vaccine effectiveness (VE) in persons aged 12-17 years (referred to as adolescents in this report) have also indicated high levels of protection against SARS-CoV-2 (the virus that causes COVID-19) infection and COVID-19-associated hospitalization (4-6); however, data on VE against the SARS-CoV-2 B.1.1.529 (Omicron) variant and duration of protection are limited. Pfizer-BioNTech VE data are not available for children aged 5-11 years. In partnership with CDC, the VISION Network* examined 39,217 emergency department (ED) and urgent care (UC) encounters and 1,699 hospitalizations† among persons aged 5-17 years with COVID-19-like illness across 10 states during April 9, 2021-January 29, 2022,§ to estimate VE using a case-control test-negative design. Among children aged 5-11 years, VE against laboratory-confirmed COVID-19-associated ED and UC encounters 14-67 days after dose 2 (the longest interval after dose 2 in this age group) was 46%. Among adolescents aged 12-15 and 16-17 years, VE 14-149 days after dose 2 was 83% and 76%, respectively; VE ≥150 days after dose 2 was 38% and 46%, respectively. Among adolescents aged 16-17 years, VE increased to 86% ≥7 days after dose 3 (booster dose). VE against COVID-19-associated ED and UC encounters was substantially lower during the Omicron predominant period than the B.1.617.2 (Delta) predominant period among adolescents aged 12-17 years, with no significant protection ≥150 days after dose 2 during Omicron predominance. However, in adolescents aged 16-17 years, VE during the Omicron predominant period increased to 81% ≥7 days after a third booster dose. During the full study period, including pre-Delta, Delta, and Omicron predominant periods, VE against laboratory-confirmed COVID-19-associated hospitalization among children aged 5-11 years was 74% 14-67 days after dose 2, with wide CIs that included zero. Among adolescents aged 12-15 and 16-17 years, VE 14-149 days after dose 2 was 92% and 94%, respectively; VE ≥150 days after dose 2 was 73% and 88%, respectively. All eligible children and adolescents should remain up to date with recommended COVID-19 vaccinations, including a booster dose for those aged 12-17 years.