A new study posted on the medRxiv* preprint server found that despite a lower coronavirus disease 2019 (COVID-19) vaccine efficacy against reinfection with the Omicron variant, these vaccines demonstrate a marked efficacy against reinfection with severe acute respiratory coronavirus 2 (SARS-CoV-2) Alpha and Delta variants, as well as the Omicron variant––lasting up to nine months, post-vaccination. Therefore, individuals who have been infected by the virus in the past must also obtain COVID-19 vaccination.
Vaccine effectiveness against SARS-CoV-2 reinfection during periods with different dominant SARS-CoV-2 variants
June 3, 2022