COVID-19 rapid testing is offered at an urgent care center in...

COVID-19 rapid testing is offered at an urgent care center in Patchogue earlier this year. Credit: Newsday/Steve Pfost

A more contagious COVID-19 subvariant now accounts for nearly 60% of all new cases in New York State, but area medical officials maintain what they've said for weeks: they don't expect it to cause a massive surge of infections, similar to what occurred across the region in December and January with the original omicron strain.

The BA.2 subvariant, which first appeared in New York in late January, now represents the majority of all new cases, surpassing the original subvariant, according to State Department of Health data.

For the two weeks ending March 26, 59.6% of all new cases across the state were BA.2, according to the data. That's an increase of 43% from the two weeks ending March 12, when the subvariant represented 41.6% of new cases. 

The rapid proliferation of BA.2, which medical professionals said spreads faster than previous variants but is not necessarily more virulent, lines up with a steady uptick in new cases statewide and on Long Island.

WHAT TO KNOW

  • Nearly 60% of new COVID-19 cases in New York State are linked to the new BA.2 omicron subvariant.
  • While BA.2 is considered more contagious than previous variants, it has yet to surge because of high regional vaccination rates and the large number of New Yorkers who were recently infected with omicron.
  • The subvariant has not produced more severe disease than earlier variants and hospitalization and deaths remain comparatively low.

On March 12, the 7-day rolling average of new cases statewide was 1.4% and 1.6% on Long Island, according to health department figures. The latest available numbers sit at 2.61% statewide and 2.75% in Nassau and Suffolk — still a far cry from early January, when the positivity rate on the Island soared well above 20%. 

The state's BA.2 data is not broken down by region.

The recent uptick of new cases also comes at a time when vaccine and masking mandates have been lifted and as booster rates have slowed across the state.

"While the proportion of BA.2 in New York has risen, it continues to rise more slowly than in many other countries," the State Department of Health said in a statement. "The department continues to monitor the situation closely.”

The department has a wastewater surveillance program used for the rapid detection and identification of variants that is being expanded to cover all counties and to include sequencing for the analysis of subvariants, officials said. 

The spread of BA.2 is even higher in neighboring areas. 

Data tracked by the Centers for Disease Control and Prevention found that between March 20 and March 26, 71% of new cases were BA.2 in Region 2, which includes New York, New Jersey, the U.S. Virgin Islands and Puerto Rico. 

Dr. Bruce Farber, chief of public health and epidemiology for Northwell Health, said BA.2's uncommonly high transmissibility may not necessarily translate to a COVID surge due to the region's high vaccination rates and the large percentage of the public with natural immunity after contracting omicron months earlier.

"Most people who have been infected by BA.1 are still fairly well immune from BA.2," Farber said. "Infections from BA.2 on top of BA.1 are quite uncommon, and when they do occur, they are very mild. I don't think we are going to have this huge surge of BA.2 infections in the next month … because our population is fairly well immune."

Farber said BA. 2 may be the most contagious form of the coronavirus that we can anticipate.

"It's hard to imagine new variants being a whole lot more contagious then BA.2," he said. "We are reaching levels of maximum contagion that you can get from a virus. It's just so contagious."

Dr. Bruce Polsky, chairman of medicine and an infectious disease specialist at NYU Langone Hospital-Long Island, said BA.2 has not produced more severe disease than earlier variants, resulting in comparatively low hospitalizations and deaths. On Wednesday, for example, the state reported 825 patients hospitalized with COVID and 8 deaths.

The current vaccine and booster regimens, Polsky said, also appear to be working well, leading to generally mild illnesses among those who contract the subvariant.

"Patients who are vaccinated are much less likely to require hospitalization and have bad outcomes when they get COVID," Polsky said. "Remember: our aim with vaccination is to prevent hospitalization and death due to COVID and not necessarily [to prevent] infections. The fact that we are not seeing much hospitalization, and this is mostly being managed as an ambulatory disease, is because of vaccination and also because omicron came across us like a wave. And there is now more infection-based immunity in the community now."

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