New York City was the primary source of coronavirus infections in the US, experts find

New York City became the primary source of COVID-19 outbreaks across the country before lockdown and travel restrictions were put in place, the New York Times reported.

Although the earliest known cases of the coronavirus were in Washington state, and the earliest known deaths in California's Bay Area, genetic samples show that most coronavirus cases in almost every region, including nearly half in major West Coast locations, could be traced back to New York City.

"We now have enough data to feel pretty confident that New York was the primary gateway for the rest of the country," Nathan Grubaugh, an epidemiologist at the Yale School of Public Health, said, according to the Times.

The findings bring more scrutiny to the city and state government responses, which waited until well into March to take aggressive action to slow the spread of the virus. Here's what New York Gov. Andrew Cuomo said about the coronavirus on March 2:

Excuse our arrogance as New Yorkers — I speak for the mayor also on this one — we think we have the best health care system on the planet right here in New York. So, when you're saying, what happened in other countries versus what happened here, we don't even think it's going to be as bad as it was in other countries.

That prediction turned out to be quite wrong. New York City, as of Wednesday, had more than 13,000 confirmed coronavirus deaths, and more than 5,300 presumed coronavirus deaths.

Researchers have previously traced a majority of New York's coronavirus cases back to Europe, rather than China, where the virus originated. That information validates the Trump administration's decision to block travel from Europe on March 13, although that decision was highly controversial and heavily criticized by the president's opponents at the time. Travel had been restricted from China on Jan. 31.

"It means that we missed the boat early on, and the vast majority in this country is coming from domestic spread," said Kristian Andersen, a professor in the department of immunology and microbiology at Scripps Research, according to the Times. "I keep hearing that it's somebody else's fault. That's not true. It's not somebody else's fault, it's our own fault."