Covid-19 vaccines deployed in England can cut transmission of the coronavirus in households by up to a half, data from Public Health England (PHE) showed on Wednesday, in addition to the protection the shots offer against symptomatic infection.

The research offers insight on one of the big unknowns over Covid-19 vaccinations - the extent to which they prevent transmission of the coronavirus - and could strengthen the case for Prime Minister Boris Johnson plans to end England's lockdown in June.

"We already know vaccines...