What to Know
- The delta variant has been found in 26% of positive NYC samples studied, up from 17.1% in the health department's last report; the week before that, delta was found in 10.6% of samples tested
- That strain now accounts for 26.8% of New Jersey samples sequenced in the last four weeks, up from 15.6% a week ago and 7.3% the week before that
- Existing vaccines have proven effective protection against the variant; virtually all new COVID deaths and hospitalizations are among unvaccinated people, the White House said this week
The highly transmissible delta COVID variant now ties with alpha as the most dominant strain in New York City, vaulting up to more than a quarter of positive samples tested in the last week, according to new health data out Friday.
As of Friday, the delta variant that first devastated India before spreading globally -- and is thought to be up to 60% more contagious than that first widely tracked alpha variant -- accounts for 26% of citywide samples tested in the last four weeks.
That's up from 17.1% in the city's variant report a week ago and up from 4.9% within about a month, a rise reflective of a national trend that saw delta emerge as America's most dominant COVID variant earlier this week.
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Delta and alpha now each represent 26% of positive samples tested in the city. Last week, delta overtook two other strains that had been more prevalent than it in New York City the week before (the so-called New York City strain that first emerged in Washington Heights before spreading elsewhere, B.1.526, and gamma, formerly known as the Brazilian strain, P.1). It'll likely overtake alpha by next week.
Scientific evidence has shown delta spreads far more easily than earlier strains of the virus and causes more severe outcomes for those infected, prompting renewed pushes at all levels of government to get people vaccinated if they haven't been.
Local
Delta, the variant that was first found in India and is now in at least 104 countries, represented 51.7% of new COVID cases in the U.S. over the two-week period that ended July 3, according to recently updated estimates by the CDC. The proportion of new cases driven by alpha was just 28.7% over the same time period.
Given the relatively minute subset of positive samples sequenced to assess potential strain variations, both CDC and local experts believe the prevalence of delta, which is classified as a variant of concern, to be much higher than reported.
The World Health Organization, which has called delta the "fastest and fittest" variant yet, expects it to become the dominant form of the disease worldwide.
Existing vaccines are expected to protect people against delta and other variants of concern that have emerged, but with just slightly more than two-thirds of U.S. adults having gotten at least one vaccine dose and less than 59% fully immunized, delta's heightened transmissibility and associated risk has renewed concerns.
The state said it's also reviewing new CDC guidance out Friday permitting teachers and students to enter classrooms this fall to ditch mask-wearing, as long as they are fully vaccinated. (Vaccines have only been approved for people 12 and up).
New Jersey has already told parents to prepare for a return to fully in-person instruction in the fall without a mask requirement. New York, on the other hand, attempted to deliver updated mask guidance at the beginning of June before walking it back as state health officials awaited a response from the public health agency.
Overall, core viral rates remain well below what they were just a few months ago across the board. Virtually all new COVID deaths and hospitalizations are among unvaccinated people, the White House said this week.
There are 1,000 counties in the U.S. where less than 30% of the population is vaccinated, federal officials say. The White House last week deployed response teams across the U.S. to those higher-risk communities.
New York City and the state's core viral rates have remained low as well, despite the surge in delta-driven cases. That said, new cases saw an uptick last week ahead of the Fourth of July holiday weekend, an increase that may be attributed to delta spreading in unvaccinated communities, according to officials.
In New York City, nearly 70% of adults have gotten at least one vaccine dose, while more than 63% are fully immunized. Statewide, those numbers are 72.8% and 66.2%, respectively.
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New York City and New Jersey Vaccine Providers
Click on each provider to find more information on scheduling appointments for the COVID-19 Vaccine.
Data: City of New York, State of New Jersey • Nina Lin / NBC
Core viral rates are consistently at or near all-time pandemic lows in New Jersey as well. Like New York, the Garden State does monitor variant data, and like New York, it has seen the prevalence of delta rise throughout the state in recent weeks.
That strain now accounts for 26.8% of New Jersey samples sequenced in the last four weeks, up from 15.6% a week ago and 7.3% the week before that.
Gov. Phil Murphy has repeatedly declared new COVID cases, hospitalizations and deaths in New Jersey to reflect "a pandemic of the unvaccinated."