When is it bad to pet a turtle w/ ur bare hands?

All reptiles carry a bacteria on them that can cause salmonella, like you get from uncooked chicken. It's fine to hold or pet turtles, just wash and sanitize you hands after, the teacher probably freaked out because you never know where a little kid is going to put their hands next (like in their mouth or rub their eyes) so when letting kids handle pets you do need to be extra careful and take extra precautions to prevent these things.