I've had a Bearded Dragon for two years now and recently got Leopard Geckos, Ball Pythons, a Boa, and a Tegu. Even if I wasn't real careful and washed my hands after handling any of them I've never had any problem and I'm someone with a bad immune system. No to mention my tegu eats raw meat and is usually fed in my bathroom or kitchen, but if people follow good hygiene with their herps I don't think there should really be much of a problem. I always wipe down all surfaces after preparing my tegu's meals and then throw the washcloth or whatever away or in the washing machine. I recently got a power/steam washer to clean out my enclosures...