Fortunately, we are mostly resistant to common bacteria, else we'd be in trouble. A guy who worked for me got shigella, they think from "organic" tomatoes. He stopped coming to work for a few days until he was well enough to call. He said it was really really bad. They put him of cipro right at the time everyone was using it because of some outbreak of whatever it was, alleged, powder of something thought to be spreading around by terrorists. Anthrax.
Sometimes the wife uses the store bags and then puts the bags in our bags because she uses the others for trash under the sink.