The variant was 27 times more likely to break through Pfizer protection from January-February and cause symptoms than it was to penetrate natural immunity from the same period.
Natural immunity from contracting coronavirus provided Israelis with longer-lasting protection against the Delta variant than two shots of the Pfizer vaccine given early this year, new Israeli research suggests.
The study by Maccabi Healthcare Service looked at individuals who had either gotten two shots of the vaccine by the end of February or tested positive for COVID-19 by that time.
It compared 46,035 Maccabi members who caught the coronavirus at some point during the pandemic and the same number of double-vaccinated people.
People who had two vaccine shots had a six-fold higher chance of getting infected with Delta than patients who hadn’t been vaccinated but previously contracted the coronavirus, according to the research.
The study, published online but not yet peer reviewed, is the largest of its kind. It doesn’t take booster shots — now widely given in Israel — into account, but given that most of the world is still giving a two-dose regimen, has international relevance.
Read the full article and study.