LONDON: The Oxford-AstraZeneca vaccine is effective against the rapidly spreading variant of coronavirus that originated in the UK, but is likely less effective against the South African strain, its manufacturers have said.

New research found that the jab combats the “Kent variant” that led to a surge of new virus cases late last year.

Data also reveals further signs that the vaccine can work to reduce transmission. Dr. June Raine, CEO of the UK medical regulator, said the results are “very reassuring.”

Meanwhile, a new report from the regulator found that the benefits of coronavirus vaccination far outweigh the minor risks involved.

The report said the “overwhelming majority” of possible side effects are only mild, such as arm pain from needles, minor headaches, chills or fever.

The reporting rate for side effects is about three per 1,000 doses — a similar level to common annual flu jabs.

But because some vaccine recipients fail to report side effects, regulators believe that about one in 10 people should expect mild side effects.

Another study from Oxford, awaiting peer review, found that people who had received a vaccine and were later infected showed lower amounts of virus matter in the body.

Prof. Andrew Pollard, chief investigator in the Oxford vaccine trial, said this led to a “reasonable assumption that vaccines could translate into a substantial reduction in transmission.”

The vaccine works just as well against the UK strain as against initial versions of the virus, meaning that other immune system elements might play an important role in protecting against the disease.

But Mene Pangalos, head of research and development for AstraZeneca, said it is likely that the vaccine will be less effective in preventing mild and moderate symptoms from the South African variant.