The guy who tested positive, one of his duties was to serve Trump his meals each day, and like Trump, none of the people who work close to the President are required to wear masks and it's reported that this person has never been seen wearing a mask. Apparently Trump was livid when he was told that this individual tested positive, demanding to know how this could have been allowed to happen.
The Person Who Serves Trump His Meals Tests Positive for the Coronavirus
http://nymag.com/intelligencer/2020/05/the-person-who-serves-trump-his-meals-has-the-coronavirus.html