Researchers said results highlight the need to continue with face coverings, social distancing and handwashing alongside vaccine programmes
Mask-wearing is the single most effective public health measure at tackling Covid, reducing incidence by 53%, the first global study of its kind shows.
Vaccines are safe and effective and saving lives around the world. But most do not confer 100% protection, most countries have not vaccinated everyone, and it is not yet known if jabs will prevent future transmission of emerging coronavirus variants.
