Just the thought of them make you itch.
But those staying at a Honolulu homeless shelter say it's not just their minds playing tricks on them. They got bite marks to prove it.
"Oh yeah I got bite all over my legs. Lotta cuts over here, cuts over there. It's really infested in there," said Michael Laimana pointing at his legs.
Laimana is one of 150 people who stay at the shelter each night. He says his bed isn't the only one with a pest problem.
A mother shared photos of her 3-year-old covered with red marks that she says are bed bug bites.
Connie Mitchell, the Executive Director at the Institute for Human Services, admits there is a problem. But she says it's almost impossible to prevent with the amount of traffic in and out of the emergency shelter.
"We definitely take it seriously. We have regular fumigation going on and we also have protocols that we follow on a daily basis as well as when we actually find that there's some kind of infestation with a particular bunk," said Mitchell.
and some of Hawaii's finest hotels have had reports of them.
So Mitchell says a problem at a homeless shelter is almost inevitable.
"Sometimes, with the folks that do come in, they're bringing them in their belongings a lot of the time if they're coming from the street. So it's very challenging to keep it in control," Mitchell said.
The shelter says they get reports of the pests about twice a week. But those staying there say they see them every night.
"I would say like 4 or 5 in the night," Laimana said.
The ongoing problem adds yet another wrinkle to the city's push to get people off of the streets and into shelters.
"It kind of is a really good illustration of some of the challenges that we have in running a shelter and being a safety net for the community," Mitchell said.
Mitchell says it's impossible to tent the shelter because the building is too large and the problem is limited to just one level where everyone sleeps.