A World Health Organization panel of experts on Wednesday recommended that the vaccine developed by AstraZeneca and the University of Oxford be used in countries where concerning new variants of the coronavirus are circulating.
The recommendation came days after a decision by South Africa to halt at least temporarily plans to roll out AstraZeneca’s vaccine.
The decision was announced after a small clinical trial indicated that the vaccine might not protect against mild and moderate cases caused by avariant of the virus first seen in that country. Researchers were unable to draw a conclusion about the impact of the variant, known as B.1.351, on the vaccine’s ability to prevent severe disease.
Despite recommending the AstraZeneca vaccine for use everywhere, W.H.O. scientists conceded that each country should take into account the state of the virus and the type of variants spreading there.
The W.H.O. has not yet granted an emergency-use listing for the AstraZeneca vaccine, a step that would set into motion the rollout of the vaccine in many lower- and middle-income countries.
The W.H.O. will separately consider the vaccine’s two manufacturers: AstraZeneca and the Serum Institute, the Indian producer that will supply many doses for the Covax initiative to bring vaccines to poorer parts of the world. The W.H.O. will weigh those decisions in the next week, with decisions expected around the middle of this month.
The W.H.O. at the end of last year approved Pfizer’s vaccine. Its decision on AstraZeneca’s vaccine is highly anticipated, because countries around the world are counting on the cheap and easy-to-store product.
Countries are expected to begin receiving their first tranches of the AstraZeneca vaccine from Covax later in February.
The W.H.O.’s decisions come as concern is rising about whether certain variants may reduce the effectiveness of Covid-19 vaccines and treatments. The B.1.351 variant has so far generated the most worry. The AstraZeneca vaccine and other leading vaccines still appear to provide strong protection against another, more contagious coronavirus variant first identified in Britain, known as B.1.1.7.
But scientists have cautioned against drawing firm conclusions from preliminary data.
“We are so in the early stages of understanding what any specific change in the virus means for the performance of one or another of the vaccines or the vaccines as a whole,” said Katherine O’Brien, the W.H.O.’s director of immunization, vaccines and biologicals, at Wednesday’s news conference.
For now, South Africa is planning to inoculate health workers starting next week with the Johnson & Johnson vaccine, which prevented hospitalizations and deaths in clinical trials in the country. The vaccine is not yet authorized there, but officials said they would use it as part of an ongoing clinical trial.
As for the AstraZeneca vaccine, South African health officials indicated on Wednesday that they were considering selling or swapping their million doses of the vaccine for different shots. W.H.O. scientists said that they were open to discussing such plans as part of the Covax initiative.
The W.H.O. panel that issued recommendations on Wednesday, known as the Strategic Advisory Group of Experts on Immunization, also advised that the AstraZeneca vaccine be given to adults regardless of their ages, breaking with a number of European countries that have opted to restrict the use of the vaccine to younger people.
The W.H.O. panel also recommended that the two doses of the AstraZeneca vaccine be given between four and 12 weeks apart. The guidance follows the release of a paper last week that found that the vaccine appears to work better when second doses are delayed. Britain and other countries have opted to delay second doses of the vaccine in an effort to get more first doses into their populations.
