One dose of Pfizer Covid-19 vaccine offers an immune response similar to that generated by infection and could also offer protection from variants to people who have previously had the virus, a British study said on Friday.
Britain in December opted to extend the gap between doses in its vaccine rollout to up to 12 weeks, with officials saying they were confident in their analysis that initial doses of Pfizer and AstraZeneca vaccines generated some protection.
The study, led by Sheffield and Oxford Universities with support from the UK Coronavirus Immunology Consortium, and released as a pre-print on Friday, found 99 per cent of people generate strong immune responses after one dose of the Pfizer-Biontech vaccine.
It backs up real-world data on Britain’s vaccine rollout from a study called SIREN which has found that one shot of either vaccine reduces severe disease.
