COVID-19 vaccines tweaked to better match today’s omicron threat are expected to roll out in a few weeks but how much wi...

U.S. regulators are telling COVID-19 vaccine makers to tweak any booster doses intended for fall so they protect against...

Pfizer says tweaking its COVID-19 vaccine to better target the omicron variant is safe and boosts protection

COVID-19 booster shots are an extra dose of the original vaccine, and some experts wonder why they weren't updated to be...

New versions of COVID-19 vaccines are now being tested in case they ever are needed to protect against mutated versions...

The lead researcher of the Oxford-AstraZeneca vaccine says she expects to have a modified jab to cope with the South Afr...