The FDA has authorised the first COVID-19 booster vaccine for teenagers in the 12 to 15 age group, giving the okay for wider use of Pfizer and BioNTech's Comirnaty shot as it tries to keep
Johnson & Johnson's also-ran COVID-19 vaccine has been cleared in the EU as a booster shot, although its role in the US could be impacted by new data on rare blood clots.
The UK government has said it will step up its COVID-19 booster vaccination dramatically, with everyone in England aged over 18 offered a third dose before the end of the month.
Preliminary study results from South Africa have suggested that antibodies stimulated by Pfizer and BioNTech's Comirnaty are less effective against the new COVID-19 variant Omicron.
The Omicron variant could supersede other strains of COVID-19 within the next few weeks to become dominant in the UK, according to an infectious diseases expert.