Interim findings from first-dose mass COVID-19 vaccination roll-out and COVID-19 hospital admissions in Scotland: a national prospective cohort study
Study (n= 1 331 993) found single dose of BNT162b2 (Pfizer) vaccine was associated with a 91% reduction in COVID-19 hospital admissions at 28–34 days post-vaccination. The corresponding effect for single dose of ChAdOx1 (Astra Zeneca) vaccine was 88%.
Source:
The Lancet
SPS commentary:
A related commentary notes that although the first dose of each vaccine probably provides substantial benefit (75% 0–6 days after the first dose), this rapid benefit against hospital admission is not plausible. Further, comparisons between the two vaccines cannot be made due to differences in storage and patient populations, which could contribute to bias.