COVID-19 mRNA Vaccines Found Effective

COVID-19 vaccines are estimated to have prevented tens of thousands of COVID-19–associated hospitalizations and fatalities during the recent pandemic.

To measure these vaccines' impact among immunocompetent adults, an Orgininal Investigation was conducted by researchers from the U.S. Centers for Disease Control and Prevention VISION Network and published by The JAMA Network Open on March 15, 2023. 

This Investigation found that the vaccine effectiveness of three doses of the monovalent mRNA COVID-19 against hospitalization was 68% for up to 4 months but decreased to 36% during the Omicron BA.4 and BA.5 era.

And Intensive care unit admission or death occurred in 21.4% of hospitalized COVID-19 patients during the BA.1 period but only 14.7% during BA.4 and BA.5 (0.17).

This study concluded that hospitalized patients with COVID-19 were less likely to be admitted to the ICU or experience in-hospital death and had a shorter length of stay during BA.4 and BA.5 predominance compared with earlier Omicron sublineage periods.