Bedbugs begone! UF fumigation school teaches low-cost control method
Tom Nordlie (352) 392-0400
Rudolf Scheffrahn email@example.com, 954-577-6312
Brian Cabrera firstname.lastname@example.org, 954-577-6363
Michael Potter email@example.com, 859-257-2398
Richard Cooper, http://www.cooperpest.com/bedbugs/bedbugs002.htm
GAINESVILLE, Fla. — Bedbugs are back, so University of Florida experts are helping revive an old method that makes it easier – and less expensive – for pest control operators to fight the blood-sucking insects.
Portable enclosures such as small trailers and closed-bed trucks can serve as fumigation chambers to treat bedding, furniture and other household items, said Rudolf Scheffrahn, a professor with UF’s Institute of Food and Agricultural Sciences.
The practice, known as commodity fumigation, enables small companies to fumigate portable items without investing in expensive tarps and seals needed to “tent” entire buildings, he said. When performed properly, commodity fumigation is safe to use in residential areas and leaves no harmful residue in enclosures.
“We thought of it as a way to help companies that are farther north and have smaller inventories of sealing and fumigation equipment to provide this specialized service,” said Scheffrahn, who works at UF’s Fort Lauderdale Research and Education Center. “It’s marrying the technique of structural fumigation with economic realities.”
This week, more than 50 pest control operators from around the world will learn to use commodity fumigation at UF’s 19th annual School of Structural Fumigation, held at the Fort Lauderdale center.
It’s the first time the school has covered bedbug treatment, he said, but it’s unlikely to be the last. The five-day event usually focuses exclusively on ridding buildings of drywood termites, but the need for bedbug control led organizers to add the new component this year.
Known scientifically as Cimex lectularius, bedbugs are flat, reddish-brown insects that can grow to the size of an apple seed. They feed on blood and have mouthparts adapted for piercing the skin, much like mosquitoes. Bedbugs are well-adapted to human environments and prefer sleeping prey, so infestations are usually located in or near beds.
In the late 20th century, bedbugs were only a minor pest problem in the United States, but in the past decade they’ve returned with a vengeance, Scheffrahn said. Infestations are found in all 50 states, everywhere from swank hotels to humble apartments.
One reason for the resurgence is that pesticides used to deal with bedbugs in the past – notably chlorinated hydrocarbons such as DDT – have been banned in the United States, due to their persistence in the environment. Ironically, this same quality made them effective against bedbugs, which can survive up to six months between meals.
Current control methods include painstaking inspections and residual insecticides – sprays and powders applied to baseboards, closets and other indoor structures to kill insects over time. But some bedbug populations have developed resistance to these products, Scheffrahn said.
“Sometimes you see 300- to 500-fold greater resistance in resistant populations compared to the old susceptible populations,” he said. “Sometimes you’d have to bathe them in insecticide and it still wouldn’t hurt them.”
Fumigation offers an alternative, he said, because bedbugs accustomed to residual pesticides have no special resistance to sulfuryl fluoride, the most widely used gas fumigant. Pest control operators have practiced commodity fumigation for years, but the technique hasn’t been commonly used against bedbugs.
The method is ideal for treating household items suspected of harboring bedbugs, because the insects dwell in nooks and crannies that might not be accessible otherwise, said Brian Cabrera, an assistant professor at the Fort Lauderdale center.
At the fumigation school, Cabrera will put commodity fumigation to the test, sealing a petri dish of live bedbugs in a mattress that will be put into a trailer and treated on Wednesday, Nov. 15. Thursday, he’ll retrieve the dish to see how the insects fare after 24 hours of exposure.
“If it works, we’ll see bedbugs lying on their backs,” Cabrera said. “What better proof is there?”
Because little research has been conducted on sulfuryl fluoride for bedbug control, Cabrera is planning a study to determine the optimum amounts and exposure times needed to kill the insects at various stages in their development, especially the eggs.
“The current recommendations on the label are based on three times the rate used for drywood termites, but where they got this rate is from a single treatment that was done on some mattresses years ago,” he said. “So we’re interested to see if that rate is the correct amount.”
Research aimed at developing innovative bedbug control methods will become increasingly important in the coming years, said Michael Potter, an extension professor of entomology with the University of Kentucky and a leading expert on bedbugs.
“I think the bedbug problem is with us to stay, and it’s going to get worse before it gets better,” said Potter, who is based in Lexington.
He said the pest control industry will become more skillful at managing bedbug infestations, but the industry faces limitations today that weren’t present a half-century ago, when bedbugs went into decline in America. Among these are restrictions on the types of pesticides and application methods that can be used, and greater expectations from consumers.
“Fifty years ago, there were times when 30 to 50 percent of the population in some cities had bedbug infestations,” he said.
Consumers with bedbug problems today should view commodity fumigation as a supplement to conventional treatment, said Richard Cooper, technical director for Cooper Pest Solutions in Lawrenceville, N.J. Alone, it’s not likely to rid a household of bedbugs because the insects and their eggs may be present in items that can’t be moved.
“Commodity fumigation can play a role in an overall bedbug management program, and it can be particularly useful for items that are difficult to treat with conventional methods,” said Cooper, whose expertise on bedbugs is recognized nationwide. “It’s a lot easier to address bedbugs in the structure if some of the complex pieces of furniture have been freed of bugs.”