• UPDATED 7PM | This story has been updated with an additional study and some commentary.

The Omicron variant of the coronavirus can partially evade the protection from two doses of Pfizer Inc and partner BioNTech's Covid-19 vaccine, the research head of a laboratory at the Africa Health Research Institute in South Africa said on Tuesday.

But the study showed that blood from people who had received two doses of the vaccine and had a prior infection was mostly able to neutralize the variant, suggesting that booster doses of the vaccine could help to fend off infection...