A [NY] state guideline says nursing homes cannot refuse to take patients from hospitals solely because they have the coronavirus.

Here is the NYT article, with much more detail.  Here is a previous MR post Claims About Nursing Homes.  Via Megan McArdle.

And from a formal study:

Twenty-three days after the first positive test result in a resident at this skilled nursing facility, 57 of 89 residents (64%) tested positive for SARS-CoV-2.