Covid-19: Single dose of Pfizer and Oxford vaccines cuts risk of hospital admission by 80% in over 80s, data suggest

Analysis by Public Health England (PHE), published as a preprint,1 estimated that a single dose of either vaccine is around 80% effective at preventing hospital admission in people aged over 80, three to four weeks after the first dose. A single dose of the Pfizer vaccine also led to an 85% reduction in deaths from covid-19 in people aged 70 and over, the study suggested. These data are not yet available for the OxfordAstraZeneca vaccine because itwas rolled out later.