People don't often consider bed bugs until they've left their mark. The appearance of flat, red welts in zigzag lines or small clusters is a key sign of bed bugs on humans. Bed bugs can also leave their bites in straight rows and, while they don't spread diseases to humans, their bites are quite irritating and scratching them can lead to bleeding and infection.
This pair of bed bug bite photos below show the immediate (left) and next day (right) reaction after feeding a colony of bedbugs from a container in the lab. (That's why they are contained in a small circular area). The hive-like immediate symptoms are replace by dark red rash type reaction the following day with inflammation and less severe redness radiating out to a larger area.
If you have bed bug bites, they may or may not look like the ones on the pictures. The bed bug bite pictures are meant as a guidance that should be used to eliminate other common insect bites. Please note that allergic reactions and a few other insect bites can look exactly like bed bug bites, so you shouldn’t make this your only step in identifying the bite. If you aren’t sure, contact your doctor and let him or her look at it. So what do bed bug bites look like? Have a look at the bed bug bite pictures below and see if they look similar to your own bites. If you have been bitten by bed bugs, then you should start bed bug bite treatment as soon as possible.
Avoidance is the best means of preventing bedbug infestation.8 While traveling, sleeping quarters and bedding should be closely inspected for signs of bedbugs. Suitcases should be placed on metal racks away from walls and furniture. Frequent travelers might consider obtaining a portable heating unit for luggage and clothing (e.g., Packtite) as an additional precaution. Items at yard sales and secondhand stores should also be carefully examined before purchase.8 All potentially infested items should be sorted and sealed in plastic bags and removed only when ready to be disinfested (see Table 36 for instructions regarding effective care of infested items). Wearing long-sleeved nightclothes can minimize exposed skin, and although insect repellants have not been shown to be reliably effective, oil of lemon eucalyptus or diethyltoluamide (DEET) might help deter bites.44,45
The diagnosis of a bedbug bite can sometimes be difficult, as bedbug bites may appear similar to the bites of other insects. A health care professional will ask detailed questions and perform a physical exam, focusing on the skin. Other organ systems will also be examined to assess for any signs of an allergic reaction or for signs of infection. No blood tests or imaging studies will be necessary. If someone is able to bring in a specimen of the insect that may have bitten them, this can be helpful in making the diagnosis.
It often seems that bed bugs arise from nowhere. The bugs are efficient hitchhikers and are usually transported into dwellings on luggage, clothing, beds, furniture, and other items. This is a particular risk for hotels and apartments, where turnover of occupants is constant. Bed bugs are small and agile, escaping detection after crawling into suitcases, backpacks and belongings. Acquiring secondhand beds, couches and furniture is another way that the bugs are transported into buildings. Bed bugs also can be carried in on one’s clothing, shoes or wheelchair. Once bed bugs are introduced, they can crawl from room to room or floor to floor. They can also be transported throughout buildings on people and their belongings.
Nightstands and dressers may need to be emptied and examined inside and out, and tipped over to inspect the woodwork underneath. Oftentimes the bugs will be hiding in cracks, corners, and recesses. Other common bed bug hiding places include: along and under the edge of wall-to-wall carpeting, especially behind beds and sofas; cracks in wood molding; ceiling-wall junctures; behind wall-mounted pictures, mirrors, outlets and switch plates; under loose wallpaper; clothing and clutter within closets; and inside clocks, phones, televisions and smoke detectors.