Looks like most of the coronavirus infections in the NYC area came from people who traveled to NYC from Europe, based on two parallel viral genome studies. This is why travel bans probably only really work in our modern world when the entire world is locked down. Also, given how transmissible the virus now appears to be, there probably is no way it ever could have been stopped, since by the time an outbreak is noticed, asymptomatic people would have always traveled out of the source region. All an earlier lockdown/travel ban would likely have done is delayed the pandemic, not denied it.
The other tidbit from the article is that genome analyses have confirmed that the virus came from bats, not a lab in Wuhan. "Maciej Boni of Penn State University and his colleagues recently used this method to see where the coronavirus, designated SARS-CoV-2, came from in the first place. While conspiracy theories might falsely claim the virus was concocted in a lab, the virus’s genome makes clear that it arose in bats."
https://www.nytimes.com/2020/04/08/...ope-genomes.html?referringSource=articleShare