Dideases that are airborne are different, such as TB. One can’t accidentally contract aids. One must seek out a carrier and willingly exchange bodily fluids. Whereas TB can strike a 3 year old kid 200 meters from the carrier.
There are a small amount of exceptions to these of course.
America is better than that, we’ve learned that rounding up and confining large groups of people is not a good solution to a problem. It isn’t even a good solution to nonviolent crime in many cases either.