Zurich/Johannesburg — AstraZeneca’s Covid-19 vaccine is worth using in areas hit by mutated strains of the virus, World Health Organization (WHO) officials and partners have said, countering concerns about reduced effectiveness that arose in a recent test.

There’s evidence the vaccine AstraZeneca developed with the University of Oxford could provide meaningful protection against severe disease caused by the highly infectious variant that emerged in SA, called B.1.351, according to Kate O’Brien, who heads the WHO’s vaccination division. The global health agency is preparing to decide on an emergency-use listing for AstraZeneca-Oxford shots made in India and South Korea...