They're hardly anything more than a rare schoolhouse pest these days, but in days gone by everyone had them. Jesus had lice. George Washington had lice. Alexander the Great had lice. Every great figure in time before industrialization and modern society had lice at one point or another in their life. It became a major problem during the 16th century on when it became coupled with the spread of Typhus. This happens to be the reason why gentlemen would shave their heads and wear a wig--lice protection. (Also, interestingly WWI slang for lice is the origin of the word 'cootie.')
There are four species of lice that are specialized to live off humans--one for the scalp, one for clothing, one for pubis hair and one specific to America.
How do creationists view this? Well, most have no clue of it, but they'd have to believe that God made not one, not two, but three species for no other purpose than to bother humans. That's too bad because their's a better that can not only help us track when we most most of our body hair, but also when we first started to wear clothing (yes, before the proverbial fig leaf)
we've been nude for around 3.3 million years based on genetic marker dating of when pubic lice diverged from other ape lice.
We've been wearing clothing for at least 107,000 years based on genetic work done on clothing lice. That's awesome.
Really interesting article about how lice might even have something to tell us about our ancestors contact with extinct species of hominids based on a 4th species of lice in the Americas: