LOL, I can picture him taking a few victory laps...like "I feel good!" https://www.youtube.com/watch?v=B1wOK9yGUYM
There are many different kinds of mites, but they tend to be species-specific. Wild birds are often loaded with mites, but not ones that go after snakes, for example.
We talk so much about mites on snakes, I can understand how you'd get the impression that they're native to U.S. but I used to deal with a number of w/c snakes to rescue & relocate...they never had mites, then I found out why...they're fortunately not native here. But plenty of other pests are, like ticks. That's why, when I take my snakes outside for sunshine, I never put them on the ground, much as they'd enjoy it. Just don't want to deal with the consequences...they can pick up some kinds of intestinal worms, for example.