Booster COVID-19 vaccine shots give 70% to 75% protection against mild disease from the new Omicron variant, the UK Health Security Agency said on Friday.
In an analysis of 581 people with confirmed Omicron, two doses of AstraZeneca and Pfizer-BioNTech vaccines provided much lower levels of protection against symptomatic infection compared to what they provide against Delta.
However, when boosted with a dose Pfizer vaccine, there was around 70% to 75% protection against symptomatic infection for people, regardless of which initial vaccine they received.