Dr. Twana Jackson prepares the child dose of the Pfizer...

Dr. Twana Jackson prepares the child dose of the Pfizer COVID-19 vaccine at the Island Park Public Library in Island Park on Dec. 22. Credit: Howard Schnapp

As the percentage of Long Islanders testing positive for the coronavirus continues to decline, numbers could within the next few weeks fall to levels from last April and May, infectious-disease experts said on Saturday.

Positivity rates had dropped below 2% by late April and to under 1% three weeks later.

Barring the emergence of a new variant or "anything else that we just don't fully understand about the virus ... I am very optimistic that at least in the short term we could have very low rates," said Dr. David Hirschwerk, medical director of North Shore University Hospital in Manhasset.

Long Island’s seven-day rate of positive coronavirus test results dropped on Friday to 5.49%, the lowest level since Nov. 30, according to state Department of Health data.

DAILY POSITIVITY RATE

Nassau: 4.1%

Suffolk: 4.9%

Statewide: 3.76%   

7-DAY POSITIVITY RATE

Nassau: 5.3%

Suffolk: 5.7%

Statewide: 4.87%

Source: New York State Department of Health

The highly contagious omicron variant, which was first detected in New York in early December and then spread rapidly, caused cases and positivity rates to soar, with the positivity rate on the Island reaching nearly 27% just a month ago.

Dr. Leonard Krilov, an infectious disease specialist and chief of pediatrics at NYU Langone Hospital-Long Island in Mineola, said that unless there's a new variant or another unexpected factor, rates likely will continue to decline more rapidly this year than they did last winter.

Omicron spreads quickly, "but it also burns out quicker, and that seems to have been the story elsewhere, and that seems to be what's happening here," he said.

High immunity levels

Hirschwerk said that, with many people contracting COVID-19 in recent weeks, and with the large majority of the population vaccinated, immunity levels are relatively high, so "you have fewer and fewer individuals left to infect."

Rates last winter also peaked in early January, but they were much lower than this year’s omicron-driven numbers, with the seven-day positivity rate in January 2021 never exceeding 10%. The seven-day positivity rate on Friday already had fallen to below the level of a year earlier.

Last year, after declining, positivity rates remained between 3% and 4% from mid-February to mid-April, before falling below 1% in mid-May and staying there through early July, when the emergence of the delta variant caused numbers to rise.

The number of new daily cases on Long Island reached a low of 30 on June 29 — compared with 943 on Friday.

Krilov said the combination of omicron burning out, and warmer weather in several weeks spurring people to spend more time in lower-risk outdoor activities, may lead to consistently low infection rates for an extended period.

"Is this really the point where it will settle and be endemic, where we’ll see periodic cases but not the major blips like we’ve seen the last couple years?" he asked. "I hope it’s the endemic phase."

Yet, Krilov added, nothing is certain with COVID-19, as previous unexpected surges demonstrated.

One factor to watch

Hirschwerk said one unknown factor in the pandemic's trajectory is immunity levels. Immunity wanes over time for those who are infected with the virus or those considered "fully vaccinated," which means two shots of the Pfizer-BioNTech or Moderna vaccines or one of the Johnson & Johnson, research shows.

There isn’t yet enough data to show how long booster shots will continue to provide strong protection for most people, and whether an additional booster may be necessary, Hirschwerk said. People with weakened immune systems already are eligible for a fourth shot.

Boosters are especially important for seniors and immunocompromised people, Hirschwerk said.

An unvaccinated person age 65 and older is 90 times more likely to die of COVID-19 than a senior with a booster shot, Centers for Disease Control and Prevention data shows. Two vaccine doses also dramatically increase the chances of survival, but less so: An unvaccinated person is about 12 times more likely to die than a senior who is fully vaccinated but not boosted. The data is from the week ending Dec. 4.

CDC data for Dec. 1 to Dec. 25 shows similarly large gaps in hospitalization rates, with two doses greatly reducing the chances of hospitalization, and booster shots decreasing the probability further.

Meanwhile, hospitalizations on Long Island continued to decline. There were 849 people hospitalized with COVID-19 on Friday, compared with 897 the day before and 2,254 on Jan. 11, which was this winter's peak.

Eleven Long Islanders died of COVID-19 on Friday, and 80 others died elsewhere in the state.

Nationwide, the number of COVID-19 deaths passed 900,000 on Friday, according to the Johns Hopkins University Coronavirus Resource Center.

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