As the specter of omicron looms large over the festive season, governments around the world are desperately trying to deploy Covid-19 booster shots in order to bolster people’s protection against the more transmissible variant.

It’s been less than a month since the new, heavily mutated Covid omicron strain was detected and designated a “variant of concern” by the World Health Organization. Before this, studies had shown that the immunity provided by Covid vaccines waned after around six months — meaning that booster shots are essential to increasing protective antibodies to fight a potential infection.

The emergence of omicron has made booster shots even more important. This is because a number of early studies — which have been published prior to peer review due to the urgency of the situation — have shown that Covid vaccines are less effective against the omicron variant compared with the globally dominant delta strain and other variants.

But the same studies have indicated that three vaccine doses — the two preliminary shots plus a booster — significantly increase the level of protection against omicron.