More producers of Covid-19 vaccines should follow AstraZeneca’s lead and license technology to other manufacturers, the World Health Organization’s head said on Monday, as he described continuing vaccine inequity as “grotesque”.

AstraZeneca’s shot, which new US data on Monday showed was safe and effective despite some countries suspending inoculations over health concerns, is being produced in various locations including South Korea’s SKBioScience and the Serum Institute of India.