After sweeping through India, a new omicron variant of the coronavirus has reached the United States, the United Kingdom, Germany, Australia and Canada, alarming virologists with a diverse array of mutations that could make current vaccines ineffective, while a different variant also goes global, The Guardian reports.

The variant omicron BA.2.75–dubbed “Centarus” by researchers–has mutated spike proteins that it uses to attach itself to cells in a human body.  Current vaccines target the spike protein of the virus to prevent the virus from multiplying in the body.  It’s unclear how effective vaccines will continue to be.

“It’s not so much the exact mutations, more the number/combination,” said Dr. Tom Peacock, a virologist at Imperial College London, who was the first to identify omicron as a potential concern back in November 2021. “It’s hard to predict the effect of that many mutations appearing together – it gives the virus a bit of a ‘wildcard’ property where the sum of the parts could be worse than the parts individually.  It is definitely a potential candidate for what comes after BA.5.  Failing that, it’s probably the sort of thing we’ll have come along next, i.e. a ‘variant of a variant.’”

The BA.2.75 variant will soon overtake the BA.2 variant as the dominant variant in India, where the BA.5 variant–a highly transmissible version–is also spreading.  In the US, the BA.5 variant is driving an increase in case counts, with BA.2.75 creeping up in the number of infections.