Some have said it must be herd immunity.
I searched on internet on herd immunity and New York,, found 31 million hits, "none" about New York.
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Some do not want to give credit Governor of New York, Mayor of New York City for management of virus, and the people complying and the top hospital system in the country.
Those who always want to say NY is bad, can never see good, although the news media and experts have over and over commented on great job done in NY.