Bed
bugs feed (on blood) mostly at night, and humans are their favorite target.
While these insects have not been a notable nuisance to humans for many
years, a more mobile society and more insect-specific pesticides are major
reasons for their comeback. (Texas Cooperative Extension photo by Bart
Drees)
(San Antonio)—Bed bugs have made a comeback in a big way, said Molly Keck, Texas Cooperative Extension entomologist.
"Not only have we had an increase in calls from Bexar County residents who have seen or been bitten by bed bugs, these bugs have become much more prevalent throughout Texas and much of the rest of the U.S, said Keck.
For many years, bed bugs were not much of a nuisance to humans, but that situation has changed, she said.
"The fact bed bugs are back—and very busy—has a lot to do with our society being much more mobile than ever before," she said. "Bed bugs are often found in hotel and motel rooms, condos, dormitories and other locations where people, especially travelers, come and go frequently."
Another likely reason bed bugs have made a comeback is due to less frequent use of broad-spectrum pesticides in the U.S., she said.
"With more insect-specific pesticides," she said, "you can't usually eliminate peripheral pests, such as bed bugs, during an application."
The bugs are often themselves "passengers" in luggage or on a person's clothes, Keck noted. While most frequently found in bedding, they also make their home in furniture, clothing and floor clutter.
"Bed bugs feed mostly at night and humans are their main target," she said. "They pierce the person's skin with their elongated beak, then gorge on the blood, like a tiny vampire."
The mature bed bug is a brown, wingless insect about three-eighths of an inch long, Keck said, but becomes larger after a blood meal. When full, the insect's body becomes swollen and elongated, and its color changes from brown to a dull red.
The bug will gorge itself with blood in three to five minutes, then crawl to a safe location to digest its meal, Keck said. Several days later, it re-emerges and looks for its next meal.
"Bed bug bites can be irritating and very uncomfortable for the victim," she added. "When they bite, the fluid bed bugs inject into a human's skin to help them retrieve blood often causes the person's skin to become irritated and inflamed."
Bed bug bites leave elongated "spindle-shaped welts" on the skin. That distinguishes them from welts left by other biting insects, such as mosquitoes or fleas, Keck said.
"The infestation usually begins in the tufts, seams and folds of bedspreads and covers, Keck said. "Later the bugs can also occupy crevices in the bedstead."
Though bed bugs are an elusive insect, there are effective ways to control them, she added.
"You need to locate their hiding places and treat them with an insecticide labeled specifically for use against bed bugs," she said. "And pesticides aren't applied to the actual bed anymore. Most applications are on the baseboards and in cracks and crevices in the home but not to the mattress, bedding or bedroom carpet."
Pesticides labeled for use against bed bugs typically have detamethrin as their active ingredient, said Keck. They normally require a second application after about 10 days to ensure the most effective control, she added.
"If you think you may have bed bugs in your home, the best thing to do is call a pest control professional who has training and experience in controlling bed bugs," she said.