Scientists do not yet know how effective the COVID-19 vaccines...

Scientists do not yet know how effective the COVID-19 vaccines are against the omicron variant. Credit: Howard Simmons

Thanksgiving gatherings and holiday season get-togethers to come likely will further an ongoing rise in COVID-19 cases, but the potential impact of the recently detected omicron coronavirus variant on Long Island remains unknown, experts said on Sunday.

The variant could already be in New York, but "if it’s going to have an impact on rising numbers, it likely won’t be for another month or so," because it would take time for it to spread, said Dr. John D’Angelo, senior vice president for emergency medicine services at Northwell Health. "Delta was here long before we actually knew it was here."

A big question mark is how effective vaccines will be against the variant, said Dr. Leonard Krilov, an infectious disease specialist and chairman of pediatrics at NYU Langone Hospital — Long Island in Mineola.

"The whole new wild card is whether this omicron variant is so much more mutated that a vaccine is less effective against it and more transmissible," Krilov said. "We’ll know more, I think, in the next week or two."

Dr. Francis Collins, the director of the National Institutes of Health, said on "Fox News Sunday" that, based on the vaccines' success against previous mutations, "we expect that most likely the current vaccines will be sufficient to provide protection."

Worries about omicron are occurring against a backdrop of a rising number of COVID-19 cases nationwide.

On Long Island, the increase in COVID-19 cases and positivity rates this autumn has roughly mirrored the pattern from last fall, when cases also began to rise around Halloween. Colder weather, which pushes people to socialize indoors where virus transmission is easier, has helped fuel the rise, Krilov said.

On Saturday, Long Island’s seven-day positivity rate rose to 4.62%, state data shows. It was as low as 2.08% as recently as Oct. 28. The seven-day statewide rate increased to 4.05%.

"I think it’s fair to anticipate there will be a slow, steady climb until we’re a couple of weeks past the new year," which is what occurred in late 2020 and early 2021, D’Angelo said.

One of the differences this year is that there have been a lot more people traveling, including to locales with lower vaccination rates, Krilov said.

In addition, fewer people are wearing masks and practicing social distancing, two of the main ways to limit transmission of the virus, said Anthony Santella, the COVID-19 coordinator for the University of New Haven in Connecticut and a professor of health administration and policy.

But Long Island’s high vaccination rates — 83% of Nassau County’s entire population is at least partially vaccinated, as is more than 75% of Suffolk’s, compared with under 70% nationwide, according to state and federal data — will help keep people from getting seriously ill, D’Angelo said.

"As the hospitalization numbers rise, it shouldn’t be as sharp a rise as we saw in the pre-vaccination days," he said.

Daily COVID-19 hospitalizations on Long Island reached a winter peak of 1,701 on Jan. 18, dropping to 50 by July 9 and then rising again as the delta variant spread, state data shows. Hospitalizations stood at 305 on Friday.

Hospitalizations and deaths have risen much more sharply upstate, where vaccination rates are significantly lower.

At Northwell, which has 11 Long Island hospitals, "the extremely large majority of people [with COVID-19] are unvaccinated, which is the minority of our population now," D’Angelo said. "Those that are vaccinated who are hospitalized aren’t as sick, but they’re the people who are very elderly with cancer or other comorbidities that make them more susceptible to being sicker than others."

He urged everyone eligible for booster shots — especially seniors and those with medical conditions linked to greater risk of severe COVID-19 — to get them.

On Saturday, there were 31 deaths statewide, including four in Suffolk, according to state data. There were more than 1,400 new COVID-19 cases on Long Island: 848 in Suffolk and 565 in Nassau.

Gov. Kathy Hochul said Friday she is so concerned that COVID-19 cases will continue to rise, and that omicron will eventually be detected in New York, that she signed an executive order declaring a "disaster emergency," allowing the state Health Department to limit or postpone elective surgeries in hospitals or hospital systems with "limited capacity."

Dr. Adhi Sharma, president of Mount Sinai South Nassau hospital in Oceanside, said Sunday that he doesn’t think elective surgeries at his hospital would be affected by the order.

South Nassau closed its Long Beach Emergency Department for nearly four days last week because of a shortage of vaccinated nurses, reopening it on Friday.

But, Sharma said, the certifications of the nurses who work on the inpatient floors and in the operating rooms of the hospital are different from the certifications of nurses who work in the emergency department.

"We don’t have a shortage on our medical wards … ," he said. "Our staffing is sufficient to provide adequate coverage for medical admissions, as well as to support the elective surgical cases. We don’t foresee any challenges there."

On Saturday, officials representing most other Long Island hospitals said they also didn’t expect a need to postpone elective surgeries.

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