Q. What does a bedbug bite look like?

A. It is often a slightly swollen, red area that can be itchy and irritating. Bites may be random or in a straight line.

Q. How do you know when a bite is from a bedbug?

A. Bedbug bites are difficult to diagnose. Sometimes reactions don’t surface until days after a bite. “You would have to look into the vacation history of the person to figure out the places where bites could have occurred,’’ said Lou Sorkin, an entomologist at New York’s American Museum of Natural History. The US Centers for Disease Control and Prevention and the US Environmental Protection Agency encourage people suspecting bedbug bites to look for clues such as the exoskeletons of bedbugs after molting; bedbugs in the fold of mattresses and sheets; a sweet, musty odor; and rusty-colored blood spots that are often excreted on the mattress or nearby furniture.

Q. Do bedbugs always bite?

A. Bugs don’t feed every night, Sorkin said. “Depending on how long that room had been vacant since the previous patron slept there, the bugs may not have been hungry.’’

Q. What’s the best way to avoid bedbugs in a hotel room?

A. “I don’t unpack anything,’’ says Jason Burnett, field manager for Dewey Pest & Wildlife in Hopedale, who found a dead bedbug in his hotel room in Ithaca, N.Y., a year ago. “I don’t use luggage racks, either. The safest place I’ve found is the bathtub.’’

Q. What precautions can you take to avoid bringing hotel bedbugs home?

A. Unpack your suitcase outside or in the garage, but not on your bed, says Jeffrey White, an entomologist with BedBug Central. Seal your clothes in a plastic bag, and put a pesticide strip in the bag to eradicate bedbugs that may be on your suitcase. Wash your clothes in hot water, and dry them with high heat.

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