The bivalent COVID-19 vaccine is recommended for use in patients aged 6 months and older by the U.S. Food and Drug Administration (FDA).^{1- 4} To understand the potential influence of the bivalent vaccine in pediatric patients, we compared the rate of COVID-19-related emergency department (ED) visits and admissions within 90 days after these patients received the bivalent COVID-19 vaccine. The comparison was made with a control group of children who received the flu vaccine but never received any COVID-19 vaccine. We studied 445,713 children aged 6 months to 17 years with data collected since each age group’s bivalent vaccine authorization.  

Our results showed that patients aged 6 months to 4 years who received the bivalent COVID-19 vaccine had a 79.6% lower rate of COVID-19-related ED visits compared to the control group (105.1 per 100,000 vs. 515.6 per 100,000). Similarly, patients aged 5 to 11 who received the bivalent COVID-19 vaccine had a 71.9% lower rate of COVID-19-related ED visits (43.6 per 100,000 vs. 155.0 per 100,000) and those aged 12 to 17 had a 66.1% lower rate (64.4 per 100,000 vs. 190.0 per 100,000).  

After accounting for patient’s prior COVID-19 infection, race, social vulnerability index (SVI), and census region of residence, the protective effect of receiving a COVID-19 bivalent vaccine remained.

 Because COVID-19-related hospital admissions were so infrequent in both the vaccinated group and the control group (91 admissions across all age groups and vaccination statuses during the study period), we were unable to identify a significant difference in the rate of hospitalization between the two groups. 

These data come from Cosmos, a HIPAA-defined Limited Data Set of more than 190 million patients from 203 Epic organizations including 1,176 hospitals and more than 25,300 clinics, serving patients in all 50 states and Lebanon. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. 

References

1. Coronavirus (COVID-19) update: FDA authorizes updated (bivalent) COVID-19 vaccines for children down to 6 months of age. U.S. Food and Drug Administration. Accessed May 2, 2023. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-updated-bivalent-covid-19-vaccines-children-down-6-months 
2. Coronavirus (COVID-19) update: FDA authorizes Bivalent Pfizer-BioNTech COVID-19 Vaccine as booster dose for certain children 6 months through 4 years of age. U.S. Food and Drug Administration. Accessed May 2, 2023. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-bivalent-pfizer-biontech-covid-19-vaccine-booster-dose 
3. Coronavirus (COVID-19) update: FDA authorizes Moderna and Pfizer-BioNTech Bivalent COVID-19 vaccines for use as a booster dose in younger age groups. U.S. Food and Drug Administration. Accessed May 2, 2023. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-moderna-and-pfizer-biontech-bivalent-covid-19-vaccines 
4. Coronavirus (COVID-19) update: FDA authorizes Moderna, Pfizer-BioNTech bivalent COVID-19 vaccines for use as a booster dose. U.S. Food and Drug Administration. Accessed May 2, 2023. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-moderna-pfizer-biontech-bivalent-covid-19-vaccines-use