CHICAGO (Reuters) – Bed bugs may be a growing nuisance, lurking in mattresses and other hiding places until emerging to seek blood for their meal, but their bites do not appear to transmit disease, researchers said last week.

Resistant to many pest control efforts, the hardy pest is spreading to hotels, homes, subways and movie theatres.

"Five-star hotels are just as susceptible as little cheap ones. People bring them in with their stuff.

"The real problem is people taking them home ... because they're so difficult to get rid of," said Jerome Goddard, a Mississippi State University entomologist who wrote a report with a colleague on the topic in the Journal of the American Medical Association. Goddard said there has been an "explosion" of bed bug infestations, with a sharp increase in reports to health departments and lawsuits against hotels. "It started in hostels and hotels, but now it's in apartments and dormitories, in houses," he said. "And it's started to get in really weird places like movie theatres and subways. (In) ships, ferries, all kind of places."

Many people do not notice the bugs' bite and have no skin reaction.

But some develop itchy bumps or ugly blisters, and a rare few have allergic reactions like asthma attacks.

Goddard sought to dispel suggestions he found in some earlier studies that bed bugs might transmit blood-borne diseases like the plague, yellow fever, hepatitis or HIV.

In the past, hepatitis was found in bed bugs in Africa. But in previous animal experiments, bed bugs fed tainted blood did not infect chimpanzees.

"At this time there's no evidence they're transmitting human diseases. That should allay fears," Goddard said.