AstraZenecas COVID-19 vaccine does more than prevent people from falling seriously ill it appears to reduce transmission of the virus and offers strong protection for three months on just a single dose, researchers said Wednesday in an encouraging turn in the campaign to suppress the outbreak.
The preliminary findings from Oxford University, a co-developer of the vaccine, could vindicate the British governments controversial strategy of delaying the second shot for up to 12 weeks so that more people can be quickly given a first dose. Up to now, the recommended time between doses has been four weeks.
The research could also bring scientists closer to an answer to one of the big questions about the vaccination drive: Will the vaccines actually curb the spread of the coronavirus?
Its not clear what implications, if any, the findings might have for the two other major vaccines being used in the West, Pfizers and Modernas.
The makers of all three vaccines have said that their shots proved to be anywhere from 70% to 95% effective in clinical trials in protecting people from illness caused by the virus. But it was unclear whether the vaccines could also suppress transmission of the virus that is, whether someone inoculated could still acquire the virus without getting sick and spread it to others.
As a result, experts have been saying that even people who have been vaccinated should continue to wear masks and keep their distance from others.