So, how about lice?

We have a problem with the Harry Potter franchise since health isn’t discussed frequently. It appears that the Hogwarts teachers simply abandon these young youngsters to their own devices, with little effort taken into ensuring their safety.
There are a lot of tiny things that they appear to overlook but are quite important. As in head lice. They never mention head lice, which you know must be a problem for the Sorting Hat. Hopefully it’s enchanted with anti-lice properties.