This has me very worried. Today I went out for groceries, and when I returned, put the groceries down, took off my shoes/sweater/pants and went to go wash my hands, I realized my cat is absolutely compelled to go over and sniff anything I've placed on the ground. If there are any droplets on my clothing or the items I've brought in, he might get infected, and then infect me later. An infection from a surface contact is mild, but an infection from a "generator" of virus (i.e. a human or a cat) can be life threatening.