Bed bugs are pretty small, and their mouths are even smaller. Bed bug saliva contains a substance that serves as a mild anesthetic, so when one bites you, it actually does you the favor of numbing your skin first. It’s very unlikely that you’d ever feel a bed bug bite when it happens. Bedbugs bite and suck blood from humans. Bedbugs are most active at night and bite any exposed areas of skin while an individual is sleeping. The face, neck, hands, and arms are common sites for bedbug bites. The bite itself is painless and is not noticed. Small, flat, or raised bumps on the skin are the most common sign; redness, swelling, and itching commonly occur. If scratched, the bite areas can become infected. A peculiarity of bedbug bites is the tendency to find several bites lined up in a row. Infectious-disease specialists refer to this series of bites as the “breakfast, lunch, and dinner” sign, signifying the sequential feeding that occurs from site to site. Bedbug bites may go unnoticed or be mistaken for flea or mosquito bites or other types of rash or skin conditions, since they are difficult to distinguish from other bites. Bedbugs also have glands whose secretions may leave odors, and they also may leave dark fecal spots on bed sheets and around their hiding places in crevices or protected areas around the bed or anywhere in the room. Bedbugs have not been conclusively proven to carry infectious microbes. scientists have found no evidence that bed bugs are capable of transmitting diseases to human hosts. For this reason, they’re considered a nuisance pest rather than a health threat. When bed bug infestations started to rise in the U.S., many health departments and agencies were slow to respond to complaints about bed bugs, because they weren’t considered a public health issue and resources weren’t allocated for combating them. But though they don’t transmit diseases, bed bugs still pose a health risk.Studies are ongoing to determine whether bedbugs may serve as carriers of other diseases. The majority of bedbug bites are not serious. The only known serious consequences are severe allergic reactions, which have been reported in some people after bedbug bites.