Before moving to Texas I lived in California and had a Desert Tortoise (registered and received legally!). A family member is now caring for her. Since moving I've cared for red-eared sliders, a Mississippi mud turtle and a box turtle that others were unable to care for. I'm a middle school...
I'm a teacher and have had red eared sliders living in a tank in my room. Students have held them and I've never had an issue. Same with my 3-toed box turtle. As long as you provide a relatively clean environment to minimize bacteria growth and wash hands (and lips apparently) after handling...