JAMA
March 22/29, 2022, Vol 327, No. 12, Pages 1109-1194
https://jamanetwork.com/journals/jama/currentissue

Research Letter
Association of Homologous and Heterologous Vaccine Boosters With COVID-19 Incidence and Severity in Singapore
Sharon Hui Xuan Tan, MPH; Rachael Pung, MSc; Lin-Fa Wang, PhD; et al.
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JAMA. 2022;327(12):1181-1182. doi:10.1001/jama.2022.1922
This study estimates SARS-CoV-2 infections and disease severity with the receipt of a booster and by type of booster.