COVID screening in India, where cases caused by the BA.2.75 variant are rising.Credit: Mohd Arhaan Archer/AFP/Gett
As countries await the end of COVID-19 surges caused by the variant BA.5, researchers are on the lookout for what will come next.
An Omicron subvariant called BA.2.75 — and nicknamed ‘Centaurus’ by some on social media — is rising fast in India. A few scientists are sounding the alarm, whereas others say it’s too early to tell whether the variant will spread widely. In India, it doesn’t yet seem to be driving up hospitalization or death rates.
BA.2.75 has been detected in more than 20 countries worldwide, and researchers are waiting to learn whether it will substantially elevate case numbers after a wave of infections with BA.5.
A slew of studies suggests that the two variants have roughly similar capacities to dodge immunity conferred by infection and vaccination. This suggests that ‘Centaurus’ might not push cases much higher outside India — at least not while population immunity is high and before the variant picks up many extra mutations.
On the alert
Surveillance of SARS-CoV-2 variants is falling by the wayside in many countries, but India seems to be at the epicentre of the spread of BA.2.75. This mutation-laden lineage evolved from the BA.2 subvariant of Omicron, which spread widely in early 2022 (see ‘Pathogen progression’).