The U.S. Environmental Protection Agency began a two-day conference in Virginia Tuesday to discuss ways to battle an itchy problem that's sweeping North America: bedbugs.

The tiny reddish-brown critters are infesting mattresses and sheets in a range of environments, from swanky hotels to homeless shelters.

For many people, the blood-sucking insects were last considered a common pest prior to the Second World War. But now their numbers have increased to the point where some public housing authorities are asking for more federal money to battle the problem.

An aide to North Carolina Congressman George K. Butterfield says the politician plans to reintroduce legislation next week to expand grant programs to help public housing authorities deal with infestations. The bill will be called the Don't Let the Bedbugs Bite Act.

Since DDT (dichloro-diphenyl-trichloroethane) was taken off the shelves in much of the industrialized world a few decades ago, there are few effective insecticides to counter bedbugs. The appleseed-sized critters have also developed a resistance to some of the chemicals on the market.

The pest management industry is pushing for federal funding to look at ways of heating, freezing or steaming them dead.

On the first day of the conference, 300 participants attended talks at the Sheraton Crystal City Hotel in Arlington, Va. Delegates will provide the EPA with advice and recommendations.

The Sheraton has had no reported bedbug problems, according to a popular online registry, so at least conference participants will be sleeping tight.

While the problem seems to be worse in urban centres, it can be a headache for anyone, said Lois Rossi, director of the registration division in the EPA's Office of Pesticide Programs.

Experts believe the bedbugs' new prevalence — not just in hotels but also homes — is because of an increase in international travel. The bugs have hitched a ride in luggage coming from countries that never eradicated them completely.

Bedbugs are not known to transmit any diseases. But their bites can cause infections and allergic reactions in some people.

With files from the Associated Press