Ok, so it appears as though you have no trouble with virae, in general, as long as they can be tracked. As long as one does not come from an illegal, you're ok with it.
Don't prove yourself to be stupider than you already have. Or do you simply not understand the word QUARANTINE??
A recent story (from Chicago, as I recall) detailed the arrival of a legal foreigner via international flight who DID have one of the really bad boys. When they fell ill, they were taken to a hospital, diagnosed, put into quarantine, and treatment begun (unfortunately the patient died). BUT....the CDC was able to, by her LEGAL paper trail, identify those who had been exposed, and quarantine and treat THEM. Only the one person died.
Try doing that if the source is an illegal.