Nits. Just looking at the word can make your head itch.
Most of us have had them and if not our kids have.
They are tricky little buggers to get rid; sometimes it would seem they can survive anything you throw at them.
Fashion guru and TV presenter, Susanna Constantine (yep, of Trinny and Susanna fame) has come forward and revealed she suffered from an extreme lice infestation for three years and was seemingly immune to treatments.
She told The Mail On Sunday: "At the age of 55, I have nits – lots of them."
"Not only am I suffering the shame of a full-blown infestation, the sort of thing associated with unkempt children in the primary-school playground, my nits have so far lasted three long years."
"At first I found it funny. I'd tease and taunt... Trinny Woodall... shaking my hair next to her. 'Urgh! Have you got nits again?' she would squeal."
"But - despite my joking - it was uncomfortable and humiliating and, for a while at least, invitations for coffee would dry up."
We feel for her, but right now we also feel our skin crawling.
In the end, it took a pretty desperate measure to get rid of the lice, Susanna paid £200 (almost $350) for a vacuum treatment which would suck up what Susanna calls "super-nits".
This extreme treatment came after other hairdressers refused to see the celebrity because of the infestation.
The treatment worked, though Susanna has been warned the fix may not be permanent and the lice could return.
Godspeed Susanna, our thoughts are with you.