Single Pfizer vaccine dose is highly protective after 21 days, research shows

A study has found a single dose of the Pfizer vaccine is ‘highly protective’ after 21 days. Photo: Ben Birchall/PA
A single dose of the Pfizer coronavirus vaccine is “highly protective” after three weeks, according to a new study.
Researchers at the University of East Anglia (UEA) said the vaccine developed by Pfizer and BioNTech was still effective after 21 days without a “top up” dose in the recommended time frame.