From flophouses to fancy hotels, bed bugs aren't fussy about where they sleep. They're also not fussy about their breeding partners either, happily mating with their own brothers and sisters if need be, new research suggests.

Researchers at the American Society of Tropical Medicine and Hygiene annual meeting in Philadelphia announced Tuesday new findings that suggest that bed bugs regularly inbreed in order to get a new colony going. But for reasons not yet understood, the inbreeding doesn't seem to hurt them.

Entomologists Coby Schal and Ed Vargo, both at North Carolina State University made their discovery after examining the genetics of bed bugs from three multi-storey apartment buildings in North Carolina and New Jersey.

They found that there were high levels of genetic relatedness within each apartment and very low genetic diversity within each building.

That told them that the infestations likely started from just one or two bugs being introduced into each apartment.

Another study by the team confirmed this same conclusion based on a study of 21 bed bug infestations from Maine to Florida, nearly all of which came from single rooms within homes.

The researchers say that because bed bugs appear to be able to withstand a high level of inbreeding and still produce healthy offspring, that allows infestations in one apartment to spread easily to other apartments in the building.

"Inbreeding gives bed bugs an advantage in being able to colonize," said Schal.

In fact, all that might be needed to start a new infestation is a single "mated" female that has been transported to a new area and is ready to lay her fertilized eggs.

"Her progeny and brothers and sisters can then mate with each other, exponentially expanding the population," Schal explained.

Cockroach populations are also able to survive inbreeding, Schal noted. Most other species begin to develop genetic abnormalities after a few generations of inbreeding that eventually brings about an end to the population.

It's not clear what mechanisms protect bed bugs and cockroaches from this.

The studies have not yet been published and are currently under peer review for the Journal of Medical Entomology.