As coronavirus numbers continue to fall, Long Island and New York City may be at or close to herd immunity or an endemic stage of COVID-19, medical experts say.
Long Island’s seven-day average of positive test results fell to 1.66% on Friday, the lowest number since July 19, state Health Department data shows.
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As coronavirus positivity and hospitalization rates continued to fall on Long Island, experts say that the region may be reaching either an endemic or herd immunity stage of COVID-19.
But they warned that rates also were very low late last spring and early summer, and a new variant or other factors could cause another increase.
Long Island’s seven-day positivity rate fell to 1.66% on Friday, the lowest level since July 19. There were 230 people with COVID-19 in the region’s hospitals, a 90% drop since Jan. 11.
"It’s clearly endemic now," said Dr. Bruce Farber, chief of public health and epidemiology for Northwell Health. "It’s in the background. The rates are exceedingly low, and we can live a life like this. If rates stay the way they are now, basically life pretty much gets back to normal."
But, Farber warned, under that definition of endemic — when the virus is still spreading but not rapidly — the region also was in the endemic stage in the late spring and early summer of last year, when rates were consistently below 1%. Then the delta and omicron variants caused surges in cases that led to a seven-day rate of nearly 27% by early January.
"Every time we’ve underestimated this virus, it’s come back to hurt us," he said.
Worldwide, where places like Hong Kong are reeling from spikes in cases, hospitalizations and deaths, COVID-19 remains a pandemic, Farber said. A pandemic is when a disease spreads widely over multiple countries.
Dr. Leonard Krilov, an infectious disease specialist and chairman of pediatrics at NYU Langone Hospital-Long Island in Mineola, said rates are so low because the large majority of residents are either vaccinated or were infected in recent months with the coronavirus. Nearly 78% of Long Islanders are fully vaccinated, although fewer than half of the fully vaccinated have received a booster shot, according to state data.
"Between the number of people infected as well as vaccinated, maybe we have reached or are close to reaching something considered as herd immunity," said Krilov, using a definition of herd immunity in which such a large percentage of the population is immune that there are no longer surges in cases.
Krilov is buoyed that, as masking and other restrictions are lifted, rates are not rising, although "the next couple of weeks will be telling" to see if the trend continues.
"We’re getting into the situation where it’s going to be around but not as severe and not as frequent, where we might see mini-clusters or outbreaks, but nothing of the magnitude where we’ve been intermittently over the past two years," he said. "That is the scenario I want to believe, and I think it is realistic."
Krilov and Farber agreed that the fall and winter will be key in determining whether rates remain low long-term. As temperatures dropped in the fall and early winter of 2020 and 2021, rates spiked as more activities moved indoors, where the virus spreads much more easily, and, in 2021, as the delta and omicron variants spread.
It’s unclear how much waning immunity — from previous infections and from vaccines — will affect rates in the coming months, Krilov said. But a possible additional booster shot at some unknown point could help mitigate the effects, he said.
No matter what, Farber said, any autumn increase in cases "won’t be nearly as bad as before" — unless there’s a new variant that emerges that immunity from vaccines or previous infection cannot combat.
"No one wants to think about that, but we would be foolish not to consider it a possibility and prepare for it, because we’ve been burned by this virus before," he said.
The 200 new cases Islandwide on Friday were a fraction of the 12,000 to 14,500 new cases on most days in late December and early January.
Farber said that for those who have received booster shots, now is as good a time as any to feel more comfortable relaxing precautions.
"If you’re ever going to go to a show, or if you’re ever going to go to a bar again, now is the time to go, because I doubt it’s going to get a lot better than it is now," he said.
In New York City, the seven-day rate rose slightly on Friday, from 1.04% to 1.09%, something that, Farber said, "we have to keep an eye on," but, he said, "I’d look at it over several weeks."
There have been similar blips in seven-day rates in New York City and on Long Island in the past few weeks, when rates slightly increased but then went back down, state data shows.
There were 230 people with COVID-19 in Long Island hospitals on Friday, down from 245 on Thursday and from a winter peak of 2,254 on Jan. 11.
Two Nassau residents and one Suffolk resident were among the 16 New Yorkers who died of COVID-19.
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