The protection afforded by two doses of the Oxford/AstraZeneca coronavirus shots, including against severe disease, begins to wane three months after the second shot, according to a new study that highlights the importance of booster programmes.
Researchers analysed data for 2m people in Scotland and 42m people in Brazil who had received two shots of the vaccine. Their findings were published in a new peer-reviewed paper in The Lancet late on Monday. The Omicron variant was not circulating during the study.
“We found waning vaccine protection of [the vaccine] against Covid-19 hospital admissions and deaths in both Scotland and Brazil, this becoming evident within three months of the second vaccine dose,” they wrote. “Consideration needs to be given to providing booster vaccine doses for people who have received [the vaccine].”