Not a viral infection like a disease. I'm talking bacterial infections, and there can be a lot of those from lizards, or anything that scuttles around on the ground in warm places.

Fun fact: Komodo dragons have a bite that will surely eff you up, even if you get away, wounded. For decades one of the main reasons was thought to be that their mouths are major breeding grounds of bacteria from old meat stuck in their teeth. Turns out that's BS. There's no old stuck meat and there's no abnormally high amounts of bacteria in their mouths. There is one other reason that is true, though.

What they do still have is a venom that mixes with their saliva that is a powerful anticoagulant. A komodo wound will bleed for hours.

Outside of those guys, most lizards are pretty safe if you avoid the teeth and claws, even if some of them are assholes.