Effectiveness of Bivalent mRNA COVID-19 Vaccines in Preventing SARS-CoV-2 Infection in Children and Adolescents Aged 5 to 17 Years.

Abstract

Importance:

Bivalent mRNA COVID-19 vaccines were recommended in the US for children and adolescents aged 12 years or older on September 1, 2022, and for children aged 5 to 11 years on October 12, 2022; however, data demonstrating the effectiveness of bivalent COVID-19 vaccines are limited.

Objective:

To assess the effectiveness of bivalent COVID-19 vaccines against SARS-CoV-2 infection and symptomatic COVID-19 among children and adolescents.

Design, Setting, and Participants:

Data for the period September 4, 2022, to January 31, 2023, were combined from 3 prospective US cohort studies (6 sites total) and used to estimate COVID-19 vaccine effectiveness among children and adolescents aged 5 to 17 years. A total of 2959 participants completed periodic surveys (demographics, household characteristics, chronic medical conditions, and COVID-19 symptoms) and submitted weekly self-collected nasal swabs (irrespective of symptoms); participants submitted additional nasal swabs at the onset of any symptoms.

Exposure:

Vaccination status was captured from the periodic surveys and supplemented with data from state immunization information systems and electronic medical records.

Main Outcome and Measures:

Respiratory swabs were tested for the presence of the SARS-CoV-2 virus using reverse transcriptase-polymerase chain reaction. SARS-CoV-2 infection was defined as a positive test regardless of symptoms. Symptomatic COVID-19 was defined as a positive test and 2 or more COVID-19 symptoms within 7 days of specimen collection. Cox proportional hazards models were used to estimate hazard ratios for SARS-CoV-2 infection and symptomatic COVID-19 among participants who received a bivalent COVID-19 vaccine dose vs participants who received no vaccine or monovalent vaccine doses only. Models were adjusted for age, sex, race, ethnicity, underlying health conditions, prior SARS-CoV-2 infection status, geographic site, proportion of circulating variants by site, and local virus prevalence.

Results:

Of the 2959 participants (47.8% were female; median age, 10.6 years [IQR, 8.0-13.2 years]; 64.6% were non-Hispanic White) included in this analysis, 25.4% received a bivalent COVID-19 vaccine dose. During the study period, 426 participants (14.4%) had laboratory-confirmed SARS-CoV-2 infection. Among these 426 participants, 184 (43.2%) had symptomatic COVID-19, 383 (89.9%) were not vaccinated or had received only monovalent COVID-19 vaccine doses (1.38 SARS-CoV-2 infections per 1000 person-days), and 43 (10.1%) had received a bivalent COVID-19 vaccine dose (0.84 SARS-CoV-2 infections per 1000 person-days). Bivalent vaccine effectiveness against SARS-CoV-2 infection was 54.0% (95% CI, 36.6%-69.1%) and vaccine effectiveness against symptomatic COVID-19 was 49.4% (95% CI, 22.2%-70.7%). The median observation time after vaccination was 276 days (IQR, 142-350 days) for participants who received only monovalent COVID-19 vaccine doses vs 50 days (IQR, 27-74 days) for those who received a bivalent COVID-19 vaccine dose.

Conclusion and Relevance:

The bivalent COVID-19 vaccines protected children and adolescents against SARS-CoV-2 infection and symptomatic COVID-19. These data demonstrate the benefit of COVID-19 vaccine in children and adolescents. All eligible children and adolescents should remain up to date with recommended COVID-19 vaccinations.

• Authors: Leora R Feldstein, Amadea Britton, Lauren Grant, Ryan Wiegand, Jasmine Ruffin, Tara M Babu, Melissa Briggs Hagen, Jefferey L Burgess, Alberto J Caban-Martinez, Helen Y Chu, Katherine D Ellingson, Janet A Englund, Kurt T Hegmann, Zuha Jeddy, Adam S Lauring, Karen Lutrick, Emily T Martin, Clare Mathenge, Jennifer Meece, Claire M Midgley, Arnold S Monto, Gabriella Newes-Adeyi, Leah Odame-Bamfo, Lauren E W Olsho, Andrew L Phillips, Ramona P Rai, Sharon Saydah, Ning Smith, Laura Steinhardt, Harmony Tyner, Meredith Vandermeer, Molly Vaughan, Sarang K Yoon, Manjusha Gaglani, Allison L Naleway
• Journal: JAMA (JAMA) Vol. 331 Issue 5 Pg. 408-416 (02 06 2024) ISSN: 1538-3598 [Electronic] United States
• PMID: 38319331 (Publication Type: Journal Article, Multicenter Study, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• COVID-19 Vaccines
• mRNA Vaccines
• Vaccines, Combined

Topics

• Adolescent
• Child
• Female
• Humans
• Male
• COVID-19 (diagnosis, prevention & control)
• COVID-19 Vaccines (therapeutic use)
• Prospective Studies
• SARS-CoV-2
• mRNA Vaccines (therapeutic use)
• Vaccines, Combined (therapeutic use)
• Child, Preschool
• Vaccine Efficacy
• United States