Study Finds Two Pfizer Vaccine Doses Offer Less Protection Against Omicron Than Against Delta – The Wall Street Journal

The first large real-world study of how vaccines hold up against Omicron found that two shots of Pfizer Inc. and BioNTech SE ’s Covid-19 vaccine lowered the risk of hospital admission by 70% for patients infected with the highly mutated variant.

The study, by South Africa’s largest private health insurer Discovery Ltd., found that while Omicron reduced vaccine effectiveness against infection to 33% from 80% for Delta, its effect on protection against hospitalization was less marked, falling to 70% from 93%.