Second booster protection wanes quickly - study

vaccine

A fourth dose of the Pfizer/BioNTech vaccine lowered rates of COVID-19 among the elderly but the protection against infection appeared short-lived, a large study in Israel has found.

The second booster's protection against infection dwindled after four weeks, Israeli researchers showed in their study published on Tuesday in the New England Journal of Medicine.

Protection against severe illness did not wane during the six weeks after the dose but more follow-up study was needed to evaluate its longer-term protection, the researchers said.

The study on 1.3 million people aged 60 and older looked at data from the Israeli Ministry of Health database between Jan. 10 and March 2, when the Omicron variant was predominant.