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The coronavirus was likely spreading in New York City as early as February, weeks before the Big Apple’s first confirmed case, according to a report citing new research.

Dr. Adriana Heguy, a member of an NYU Grossman School of Medicine team studying the genomes of coronaviruses from city patients, told the New York Times that early findings indicate the virus was in the city well before a Manhattan woman in her 30s became the city’s first official patient on March 1.

Heguy and her team learned of the discrepancy by analyzing the different viral mutations between the city cases, according to the report.

Certain viruses, Heguy told the paper, shared mutations not seen elsewhere.

“That’s when you know you’ve had a silent transmission for a while,” she said.

A separate group of researchers from the Icahn School of Medicine at Mount Sinai, who are also studying the genomes of city coronavirus patients, determined that early city cases were not linked to later ones, which they found came from Europe.

Two weeks after the first cases at Mount Sinai Hospital, “we started seeing viruses related to each other,” Ana Silvia Gonzalez-Reiche, a member of the Mount Sinai team, told the Times.

The newer viruses closely mirrored those found in Europe, the Mount Sinai researchers found, indicating “a period of untracked global transmission between late January to mid-February,” according to their study, which is awaiting peer review.

The Mount Sinai team analyzed 84 distinct COVID-19 genomes out of 800 confirmed cases treated at the Mount Sinai Health System, the hospital said in a press release.

The results of their research indicate that the coronavirus “came to New York City and environs predominately via untracked transmission between the United States and Europe, with only limited introduction from China, where the virus originated,” Dr. Viviana Simon said in a statement.

“Only one of the 78 cases studied was infected with a virus that was a clear candidate for introduction from Asia, and that virus is most closely related to viral isolates from Seattle, Washington,” said Simon.