Durability of Bivalent Boosters against Omicron Subvariants

This study assesses the long-term effectiveness of Moderna and Pfizer-BioNTech bivalent Covid-19 boosters, which include components targeting both the ancestral SARS-CoV-2 strain and the Omicron BA.4-BA.5 subvariants. Using data from over 6 million North Carolina residents between September 2022 and February 2023, the article analyzes outcomes such as infection, hospitalization, and death across subvariant waves (BQ.1-BQ.1.1 and XBB-XBB.1.5). Booster effectiveness peaked around 67% after 2 weeks and waned over 20 weeks. The results show durable protection against severe infection and death, with slightly better performance for Moderna boosters and among previously infected individuals.

This study assesses the long-term effectiveness of Moderna and Pfizer-BioNTech bivalent Covid-19 boosters, which include components targeting both the ancestral SARS-CoV-2 strain and the Omicron BA.4-BA.5 subvariants. Using data from over 6 million North Carolina residents between September 2022 and February 2023, the article analyzes outcomes such as infection, hospitalization, and death across subvariant waves (BQ.1-BQ.1.1 and XBB-XBB.1.5). Booster effectiveness peaked around 67% after 2 weeks and waned over 20 weeks. The results show durable protection against severe infection and death, with slightly better performance for Moderna boosters and among previously infected individuals.