Estudo observacional no Catar mostrou que a efetividade da vacina da Pfizer contra qualquer infecção por SARS-CoV-2 caiu para 20% entre o 5º e o 7º mês após a segunda dose, mas a efetividade contra Covid-19 grave permaneceu alta.

Waning of BNT162b2 Vaccine Protection against SARS-CoV-2 Infection in Qatar – New England Journal of Medicine

Conteúdo relacionado: Cohort study: Pfizer vaccine effectiveness against any infections declined from 88% during the first month after full vaccination to 47% after 5 months. Vaccine effectiveness against hospital admissions remained high; 87% within 1 month, and 88% at 5 months after full vaccination, with no significant waning.

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In this 900,000-participant study in Qatar, vaccine effectiveness peaked at 77.5% in the first month after the second dose. The effectiveness fell to as low as 20% in months 5 through 7 after vaccination. #Covid19vaccine #IDTwttier https://t.co/TeDcLLftIH pic.twitter.com/pEBoxs6Hmr

— NEJM (@NEJM) October 6, 2021