The negative reaction that will backfired on the U.S, is that pharmaceutical , medical and health company have been outsourcing their manufacturing to China for decades. Any thing from vaccines to vitamins and all else between.. The first response and need will be China it's self and the care of it's one billion citizens. Which all compounds to a serious shortage to the U.S. if the coronavirus overtakes this country.
The U.S. already have a limited supply of vital pharmaceutical supplies, that is a know fact. With the increases of border crossing, a large part of medicine and other disease and health precautions have been directed to those migrants. That goes far in draining the needs of American. Just to note: breathing mask, the good kind that actually work, are getting hard to find lately. Most all made in China, of course.
Not only the very old or very young, but all people can become victims of a potential out break. A vaccine has not been developed as yet.