A new study suggests that the protection provided by a COVID-19 booster shot wanes after about four months, highlighting the need for additional booster doses to maintain high levels of immunity against the virus. The study, published in the journal JAMA Internal Medicine, examined data from over 4 million U.S. adults who received a booster dose of either the Pfizer-BioNTech or Moderna vaccine between August and December 2021. The researchers found that the effectiveness of the booster shot in preventing COVID-19 infection declined from 87% in the first month after vaccination to 57% four months later. The decline in effectiveness was similar for both the Pfizer-BioNTech and Moderna vaccines. The study also found that the booster shot was less effective in preventing severe COVID-19 outcomes, such as hospitalization and death. The effectiveness of the booster shot in preventing severe outcomes declined from 94% in the first month after vaccination to 78% four months later. The researchers say that their findings suggest that additional booster doses may be needed to maintain high levels of protection against COVID-19, especially for people who are at high risk of severe outcomes. .
Study: COVID-19 Booster Shot Protection Wanes After 4 Months
