Omicron Variant

New NY Breakthrough Data Show Omicron's Stunning Impact; COVID Hospitalizations Top 12K

To be sure, COVID rates are still increasing -- total hospitalizations topped 12,000 Monday for the first time since April 28, 2020 -- but the rate of growth in new daily cases and hospitalizations appears to be slowing

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What to Know

  • Breakthrough COVID infection rates per 100K NYers surged by more than 7x last month, while breakthrough hospitalization risk grew by 4x; the total numbers are minimal compared with risk to unvaccinated
  • Now, though, core viral rates are seeing slower rates of growth, even though they remain high; New York state saw total hospitalizations dip Sunday for the first time in three weeks but it rose by 275 Monday
  • Still, the net increase in hospital admissions reported Monday was the lowest it's been so far in 2022 aside from that Sunday decline, while Monday marked the 2nd straight day of below 20% statewide positivity

Newly released data on New York breakthrough infections highlights in stark reality the viral force that crippled workforces for virtually every key industry last month, while COVID rates in the one-time epicenter show potential signs of improvement.

Fueled by the more vaccine-resistant omicron variant, the daily rate of new COVID infections per 100,000 fully vaccinated New Yorkers grew by more than seven-fold over the course of December, from 29.8 new cases per 100,000 inoculated residents the first week of the month to 223.3 the final week, state data shows.

The risk of becoming a new COVID case was exponentially higher for unvaccinated adults, who had a 1,583.1 rate per 100,000 new case rate by the end of December. That's more than six-and-a-half times higher than the new case rate per 100,000 that group had the first week of December (239.6, which, notably, was higher than where the rate per 100,000 fully vaccinated ended the month amid the surge).

Overall, the age-adjusted vaccine effectiveness rate for new cases ended December at 77.8%, lower than where it started (80.9%) but a marked uptick over the previous two weeks of data (75.4% the week of Dec. 13, 76.1% the week of Dec. 20).

vax effectiveness december 27 case
New York State Department of Health
New daily COVID cases over time by vaccination status

Vaccine effectiveness remained exceptionally high among the fully vaccinated through omicron's December tear, with just 4.59 fully vaccinated New Yorkers of 100,000 ending up hospitalized for COVID the week of Dec. 27.

That's up from 1.17 the first week of December, but still almost 13 times lower than the hospitalization rate per 100,000 unvaccinated New Yorkers (58.27). For the latter group, the rate of COVID hospitalization per 100,000 more than tripled over the course of December.

vaccine effectiveness hospitals
New York Department of Health
New daily COVID hospitalizations over time by vaccination status

Overall, the state reported a 92.3% age-adjusted rate of vaccine effectiveness against COVID hospitalization to end the month of December, a dip from a 95.1% rate the week of Dec. 6 but not a particularly worrisome one.

Anecdotally, effectiveness rates remain highest among those who have gotten boosters, and while state data doesn't incorporate that into its fully vaccinated definition, data broken out by age group shows the highest sustained efficacy among adults aged 65 and older.

Estimated weekly vaccine effectiveness against both new cases and hospitalizations within that demographic declined by just 0.5% in December, while

The drops in vaccine efficacy against COVID infection for fully vaccinated people aged 18 to 49 and 50 to 64 were a bit higher but similar to one another, about 3.7%, in December. The drop in efficacy against hospitalization was slightly higher (3.8%) for the older group versus the younger group (3.2%).

Estimated vaccine effectiveness for reducing cases and hospitalizations with laboratory-confirmed COVID-19, by age group, NYS

vaccine efficacy by age omicron wave
New York State Department of Health
For grey shaded areas, data are still accruing and estimates are subject to most change.

Efficacy against severe cases for both remained at 91% or higher. And it's likely a significant number of vaccinated New Yorkers who ended up hospitalized with COVID last month had one or more underlying conditions that landed them there.

As Gov. Kathy Hochul and others have pointed out, the hospitalization totals alone, while the highest since April 2020, do not tell the whole story.

More than 40% of COVID patients hospitalized statewide were admitted to hospitals for non-COVID reasons according to preliminary data Hochul released late last week. Their virus diagnoses were discovered during routine testing as part of the admissions process. In New York City, half of COVID patients admitted to hospitals on Jan. 4 and Jan. 5 were admitted for non-COVID reasons, she said.

The governor noted some data points that had her "cautiously optimistic" that the peak might come soon, but said she wasn't yet willing to declare any sort of trend. Another hopeful sign came over the weekend, with New York state COVID hospitalizations dipping in Sunday's report for the first time in three weeks.

That number bounced back up by nearly 300 admissions on Monday though, with Hochul reporting total hospitalizations had topped 12,000 (12,022). That's the highest statewide total since April 28, 2022, but the net increase in admissions was the lowest it's been so far in 2022 aside from that Sunday decline in numbers.

In other words, discharges are accelerating faster than admissions, which underscores oft-cited evidence that even people hospitalized with COVID are less severely ill than in previous waves and getting out of the hospital faster.

Another hopeful sign: Fewer than one in five New York COVID tests came back positive Sunday for the second straight day, the governor's Monday release said.

New York City viral rates indicate similar trends over the last few days, though weekend data is notoriously difficult to rely upon especially as it relates to cases. The rolling weekly case average is up 19% over the averages for the prior four weeks, though that percentage was as high as nearly 125% just before Christmas.

The hospitalization rate is up about 11% by the same parameters. Four days ago, that rolling rate was 62%. And in terms of rolling transmission rates, about 2,560 per 100,000 NYC residents were infected with COVID in the latest seven-day period.

While incredibly low, it's a marked reduction from the 3,400-plus per 100,000 becoming infected just a week ago.

nyc covid transmission rates
NYC Department of Health and Mental Hygiene
NYC rolling COVID case rate
NYC Health Department
NYC rolling COVID case rate
nyc hospitalization rate
NYC Health Department
NYC rolling COVID hospitalization rate

To be sure, viral rates are still increasing across all key indicators, but the rate of growth appears to be slowing -- drastically so, at times -- over the last week. Time will tell as to whether it's a promising trend or merely a blip in this latest wave.

Dr. Anthony Fauci told News 4 Friday he thought omicron's peak could be a matter of weeks away -- and CDC Director Dr. Rochelle Walensky told reporters it was possible (though far from certain) cases could drop as quickly as they rose.

Nationally, omicron's prevalence is believed to be as high as 97%, though the CDC has yet to update its data for the past week.

It estimates the variant's share of current New York region cases, which for the agency's purposes includes New Jersey, the Virgin Islands and Puerto Rico in addition to the Empire State, to be as high as 99.1%.

New York state-specific data put omicron's share of genetically sequenced positives uploaded to the GISAID database, the world's largest repository of its kind, at 95.9% of cases over the last two-week period, according to the governor's office.

All in all, it took omicron barely a month to establish total dominance across the United States. The first confirmed U.S. case was reported on Dec. 1, while New York's first confirmed omicron case was reported a day later.

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