What do we know about two new versions of Omicron variant spreading in New York

Two new versions of the BA.2 Omicron coronavirus variant are driving new cases in New York, according to officials, helping the region become a national Covid hotspot once again. So far, the variants, BA.2.12 and BA.12.1, may be the fastest-spreading forms of the virus yet, though they don’t appear to cause more severe cases of coronavirus.

State health officials announced the two variants on Wednesday, arguing “these highly contagious new variants are likely contributing to the rising cases.”

The pair of variants was responsible for more than 70 per cent of new cases in central New York State in March, a figure now above 90 per cent. The same strains of Covid have been identified in 30 other US states and 40 other countries.

“While these subvariants are new, the tools to combat them are not,” State Health Commissioner Dr Mary T Bassett said in a statement on Wednesday. “These tools will work if we each use them: get fully vaccinated and boosted, test following exposure, symptoms, or travel, consider wearing a mask in public indoor spaces, and consult with your healthcare provider about treatment if you test positive.”

The variants both evolved from the BA.2 Omicron variant, a descendant of the BA.1 version of Omicron that drove the massive spike in cases over the winter.

The new variants have a roughly 25 per cent “growth advantage” over BA.2, until then the most contagious form of Covid. That means these new forms could be more likely to reproduce and become the dominant form of coronavirus than other strains.

“It’s just a reminder that we’re not out of the woods with regard to this virus, and people should continue to take precautions and to get fully vaccinated if they haven’t completed their course,” Kirsten St George, a virologist for the state, told The New York Times on Wednesday.

Though perhaps not as severe, the new variants are pushing cases back up in New York to levels seen during 2021’s Delta wave.

Craig Spencer, director of global health in emergency medicine at Columbia Medicine in New York said this week it appears cases in the state are largely spreading among younger people who require less hospitalisations, and that the state’s hospital system has plenty of capacity at the moment, compared to the “tsunami” of cases over the winter.

“I remain hopeful this uptick in cases won’t translate into a big increase in patients requiring hospitalization,” he wrote on Twitter on Monday. “Hospitalisation isn’t the only thing that matters. But it matters, a lot.”

He did note, however, that because of the rise of rapid at-home Covid tests, state data is likely an undercount because these tests aren’t being recorded in government systems.

The surging set of variants comes a month after New York state and New York City both lifted key parts of their indoor mask and vaccine proof mandates.