The latest increase in COVID-19 cases throughout the region and...

The latest increase in COVID-19 cases throughout the region and across the state has been fueled by two newly identified omicron subvariants. Credit: Getty Images/Spencer Platt

A new and more contagious omicron subvariant has increased from about 5% to more than 18% of cases on Long Island and in New York City, but it has not caused a comparable rise in hospitalizations and deaths.

Between the month of March and April 20, the subvariant BA.2.12.1 saw a nearly fourfold increase to account for almost one of every five new cases in the region, according to data released by the New York State Department of Health.

The percentage rose from 4.9% to 18.4%.

Some regions upstate saw far higher numbers. The subvariant accounted for 77% of new cases in Central New York, more than 50% of cases in the Finger Lakes, and a large percentage in the Capitol region, Mohawk Valley and Southern Tier as well.

Long Island and New York City were lumped together as one region since most Long Island specimens are sequenced in New York City, the health department said.

Dr. Bruce Farber, chief of public health and epidemiology for Northwell Health, said the key question would be the amount of immunity in the population from previous infection by the omicron strains. That would limit the spike in cases, he said.

The New York State Department of Health said earlier this month that BA.2.12.1 and another newly identified subvariant, BA.2.12, grow at a rate of 23% to 27% faster than the original BA.2 subvariant.

But, said Farber, the symptoms of people infected with BA.2.12.1 generally “are mild, and I think that’s the good news."

Dr. Alan Bulbin, director of infectious disease at Catholic Health St. Francis Hospital & Heart Center in Roslyn, said that he's uncertain about how to explain the subvariant's quicker growth upstate, including in counties that according to the U.S. Centers for Disease Control and Prevention have some of the highest rates of community spread in the country.

He and Farber agreed that BA.2.12.1 will become more prevalent on Long Island.

“There’s no way to hide from these subvariants or for that matter from any variant,” Farber said.

However, both experts said they were optimistic about the current spike plateauing soon, with Bulbin noting that we are seeing the tail end of the omicron surge that hit record levels in January.

In the latest COVID-19 indicators released by the state, some numbers continued to climb. The seven-day average for positivity on Long Island was 6.71%, compared to 4.62% two weeks ago.

But other indicators dropped: the number of new daily cases was 354 in Nassau County, compared to 401 two weeks ago. Suffolk County showed 310 new cases; two weeks ago, that number was 343.

The daily new case numbers are widely considered to be undercounts given the proliferation of at-home tests that are not reported.

The number of people hospitalized statewide with COVID-19 on Sunday was 1,588, an increase of 63 from the previous day. Two weeks ago, that figure was 1,060. There were more than 12,000 people hospitalized statewide at the peak of the omicron surge in January.

Throughout the state on Sunday, 10 people — including one in Suffolk — died of causes linked to the virus.

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