Herd immunity with these covid vaccines? “Probably not”. Massimo Galli, head of infectious diseases of the Sacco di Milano, thus expresses himself at Otto e mezzo on the effectiveness of the current coronavirus vaccines. “I absolutely agree on the need for the vaccine to reach everyone”, says Galli, referring to a topical issue. “Problem within the problem: what we have now is a very good vaccine for a virus that was around a year ago in China. The landscape is now very varied and this makes it difficult to think with the current vaccine. The work published in the NEJM of 5 May says the Pfizer vaccine is 97% effective for avoiding graveyard and hospital resuscitation for any variant, “he adds. “If we consider the infection with the South African variant the efficacy rate is much lower. The question is: with this vaccine we get herd immunity, can we keep the virus from circulating? The answer is probably no,” he says again. “We need to consider the variants and the need for what we are using now to be updated in a more or less short time”.