So long as you wash the wound (if any) to prevent any infections, I don't believe so. The most an injury could do is just hurt real bad and possibly require stitches but that's the worst case scenario from the largest reptiles, and they still won't kill you anyway. If you're just fiddling around with boas, ball pythons, bearded dragons, etc you should certainly be fine. The reptile keeping community has made a point in stating over and over again that these animals are not dangerous, after all. Take some hand sanitizer with you, and just be wary if you ever decide to hold a large, aggressive monitor lizard! (They won't kill you, but they can hurt!)