Odds of testing positive for COVID-19 after receiving 3 vs 2 doses of Pfizer-BioNTech vaccine

Editor's Note

The findings of this study by Israeli and Yale University researchers suggest that the waning of vaccine-induced protection against COVID-19 is counteracted in the short-term by a third dose of the Pfizer-BioNTech vaccine.

In this case-controlled analysis of 306,710 Israeli adults 40 years and older, there was a significant 83% to 87% reduction in the odds of COVID-19 infection after at least 2 weeks following the third-dose booster, compared with the two primary doses.

Those who received the third dose also had 92% to 97% lower odds of hospitalization after 14 days than those who received just two doses.

Further monitoring is needed to determine the duration of immunity following the third-dose booster, the researchers say.