Kissing bug: The insect that transmits the parasite Trypanosoma cruzi, which causes Chagas disease (American trypanosomiasis). The bug "kisses" people, especially babies, on the lips while they are asleep, infecting them with the parasite.
The bug (technically a reduviid bug) lives in cracks and holes of substandard housing in South and Central America. The bug becomes infected after biting an animal or person who already has Chagas disease. The infection is spread to people when an infected bug deposits feces on a person's skin, usually while the person is sleeping at night. The person often accidently rubs the feces into the bite wound, an open cut, the eyes, or mouth. Animals can become infected the same way, and they can also contract the disease by eating an infected bug. The parasite can also be transmitted by blood transfusion and it can cross the placenta during pregnancy to infect the fetus.
It is estimated that 20 million people in the Americas have Chagas disease. Rural families there can lower the risk of the deadly Chagas Disease by not sleeping in the same room with chickens and dogs. Chickens and dogs kept in rural bedrooms form a reservoir for the insect that carries the parasite, Trypanosoma cruzi, that causes Chagas disease.