Beating bedbugs

Bedbug infestations are notoriously hard to eliminate, but University of Florida (UF) researchers have developed a low-cost, low-tech method to kill the bloodsucking insects in furniture and bedding, using heat.

With less than $400 (£245) in equipment they created a portable chamber big enough for a bed or dresser. Heaters inside the chamber gently raise its air temperature to a minimum of 113^oF - enough to destroy the insects but not damage the items.

Treatment takes from two to seven hours, said urban entomologist Phil Koehler, a professor with UF’s Institute of Food and Agricultural Sciences. The method killed 100 per cent of bedbugs in nine out of 11 trials conducted in dormitories and apartments.

’You’re very limited in what you can do to fight bedbugs,’ he added. ’This is a good way to relieve infestations in bedding and other items people have close contact with, and it controls all life stages of bedbugs.’

The UF researchers developed their method as an experiment, to see if portable heating chambers could be used together with pesticides to treat rooms quickly.

The key, Koehler said, is raising all air in the chamber to a minimum of 113^oF. The researchers used digital thermometers with probes placed in some of the treated items so they could continuously monitor temperatures inside the chamber.

To ensure effective treatment, the probes must be put in places the heat is least likely to reach. ’It’s somewhat like cooking a turkey,’ Koehler added.

Clothes, sheets and other bedding can also be placed in a dryer at high heat for about 15 minutes to kill all bedbugs, said Koehler.

For the trial, researchers placed vials of live bedbugs inside furniture items, and then assembled the chamber around the furniture, said Roberto Pereira, a research associate scientist who works with Koehler.

The method killed 100 per cent of the bedbugs in rooms with carpeted floors, but only killed about 83 per cent when used on tile because the heat wasn’t contained effectively, Pereira added.

The researchers don’t plan to develop a commercial product but will continue researching the effects of heat treatments on bedbugs, Pereira said.

Portable heat chambers may be best suited for situations where bedbugs are known to infest a small area, such as a single piece of furniture or a suitcase, said Michael Botha, president of Sandwich Isle Pest Solutions, in Pearl City, Hawaii.

Botha added that his company is experimenting with chambers for treating luggage because travellers sometimes unwittingly pick up bedbugs in hotels and bring them home in suitcases.