Direct translation?

I just had a French guy ask me what it means in English to “have crabs.”

Aaahahahahahaaa. Oh shit I died laughing. I tired to explain to him about bugs and hair, but he didn’t understand and thought I was telling him that there were spiders on his head. Finally after a series of gestures and some interesting facial expressions, he understood. He didn’t think it was quite as funny as I did though. Poor guy.