But the officials said they've seen no evidence that the New York City variant is deadlier or more vaccine resistant than earlier forms of the virus.
Dr. Jay Varma said that the strain that started in the UK (B117) and the one that originated in NYC (B1526) are both making up 51% of cases.
The rest are what Dr. Varma called "COVID classic."
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The NY variant represents about 39% of all samples sequenced in the past week, compared to 31% the week before, suggesting it "is a more infectious variant."
"Our preliminary analysis does not show that this new strain, B1526, causes more serious illness or reduces the effectiveness of vaccines. Important to emphasize this is preliminary. We are working closely with academics, neighboring states, with CDC to collect and analyze more data," Dr. Varma said.
The UK variant represents about 12% of all samples sequenced in the past week, compared to 8% of the week before.
So far, the variants have been found to spread more easily but city officials reminded city residents to keep doing what they are doing.
Residents are reminded to wear a mask, wash their hands, social distance, and stay home if you are sick.
Deaths and serious hospitalizations have been decreasing in the city and officials attribute that to the vaccination of high-risk people.
New York City is one of the only cities in the nation that tracks the prevalence of the variants weekly.
The positivity rate in the city is currently 6.23%. Statewide positivity is at 3.16%.
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