This is more good news too.
Out-of-date information may be deterring people from being vaccinated.
www.bbc.co.uk
Regular testing of participants in the Oxford-AstraZeneca vaccine trials, with or without symptoms, found positive tests fell by more than half.
And this suggested "the potential for a substantial reduction in transmission", the team reviewing the trial results said.
The Pfizer-BioNTech trial participants, meanwhile, were tested only if they had symptoms.
But a later
study of 40,000 health workers in England suggested one Pfizer-BioNTech dose cut the risk of infection - symptomatic or otherwise - by 70%, and two doses by 85%.
People
e living with vaccinated NHS staff in Scotland were considerably less likely to catch the virus than those living with unvaccinated health workers, providing direct evidence the jab can protect others.
And a separate
analysis of the test results of hospital workers in Cambridge found a 75% decrease in asymptomatic infections after vaccination.
In Israel, the Pfizer-BioNTech vaccine appeared to reduce all infections by as much as 90%, although the Ministry of Health could not be certain of the precise number as not everyone came forward for asymptomatic testing.
And, a different Israeli study found, the infections there had much lower "viral loads" - people shed less virus, meaning they would be less contagious as well as at lower risk of becoming ill.
Similar conclusions have been drawn in studies of patients in the US and
care-home residents in England.