As the percentage of Long Islanders testing positive for the coronavirus continues to decline, numbers could within the next few weeks reach levels from last April and May, a leading infectious-disease expert said on Saturday.
“The main driver of increased rates would be the emergence of a new variant,” said Dr. David Hirschwerk, medical director of North Shore University Hospital in Manhasset. “If that doesn’t happen, I am very optimistic that at least in the short term we could have very low rates.”
Long Island’s seven-day positivity rate Thursday dipped below 6% for the first time since early December It stood at 5.81%, the lowest seven-day average of the percentage of positive coronavirus test results since Dec. 1.
New York City’s rate was even lower: 3.35%, by far the lowest in the state. Data for Friday will be released later today.
The highly contagious omicron variant caused cases and positivity rates to soar on Long Island and nationwide, with the positivity rate on Long Island reaching nearly 27% just a month ago.
Hirschwerk predicts, “if there are no new surprises,” rates may decline more rapidly this year than they did the past mid- and late winter.
High immunity levels
With the large majority of the population vaccinated, and with many unvaccinated people contracting COVID-19 in recent weeks, immunity levels are relatively high, so “you have fewer and fewer individuals left to infect,” he said.
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 Thursday already had fallen to roughly the same level as exactly a year earlier.
Last spring started with a positivity rate above 4% but ended at 0.4%, with the positivity rate staying below 1% from mid-May through early July, when 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 856 on Thursday.
Hirschwerk cautioned that many unknowns remain. COVID-19 “has presented a lot of surprises each step of the way,” he said.
Waning immunity
One factor is immunity levels, he said. 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 for older adults, with two doses greatly reducing the chances of hospitalization, and booster shots decreasing the probability further.
The nation surpassed 900,000 COVID-19 deaths on Friday, according to the Johns Hopkins University Coronavirus Resource Center. It took only 51 days for the country to go from 800,000 to 900,000 deaths.
With the number of COVID-19 cases declining rapidly, Hirschwerk said it likely would take longer for the country to reach 1 million deaths.
Check back for more on this developing story.
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