Kissing bugs, scientifically known as the Triatominae subfamily, are blood-feeding insects also referred to as assassin bugs or conenose bugs. They feed on the blood of vertebrates, including humans and animals. Found across the Americas, 11 species are identified in the United States, predominantly in southern states like Texas, New Mexico, and Arizona.
Understanding Kissing Bug Flight
Adult kissing bugs can fly, though they are not strong fliers and are more often seen walking. Nymphs lack wings and can only crawl. Adults typically fly around dusk and early evening, especially during warmer months from May through October. These flights help them seek hosts, mate, and disperse to new areas.
Kissing bugs are attracted to artificial light sources, which can draw them towards homes. They may then crawl under doors or through gaps to enter residences. In regions like southern Arizona, active flight periods occur from mid-May through mid-July, peaking in late June to early July.
Identifying Kissing Bugs
Adult kissing bugs typically measure 1/2 to 1 inch long, about the size of a penny. They usually have dark brown or black bodies, often with a striped band of red, orange, or yellow markings around their abdomen. One species, Triatoma protracta, found in the southwestern United States, may have a light-brown band or no band. Their head is cone-shaped and elongated, with thin antennae and slender legs. Kissing bugs have a thin proboscis, or mouthpart, which they tuck under their body.
They are nocturnal, active at night, and hide during the day in cracks, crevices, under porches, between rocky structures, or in animal burrows and nests. It is important to distinguish them from look-alike bugs, such as squash bugs or stink bugs, which feed on plants or other insects and do not transmit the parasite causing Chagas disease.
The Threat of Chagas Disease
Kissing bugs can transmit the parasite Trypanosoma cruzi, which causes Chagas disease. Transmission primarily occurs when an infected bug bites a person or animal, then defecates near the bite site. The parasite enters the host’s body if the feces are rubbed into the bite wound, mucous membranes like the eyes or mouth, or other skin openings.
Chagas disease has two phases: acute and chronic. The acute phase occurs shortly after infection, lasting weeks or months, often with mild or no symptoms like fever, body aches, rash, or swelling at the infection site. Romaña’s sign, characterized by eyelid swelling, can occur if the parasite enters through the eye.
The chronic phase, developing years or decades later, can cause serious health problems in 20-30% of infected individuals. These include cardiac complications like heart failure and irregular heartbeats, or digestive issues such as an enlarged esophagus or colon. Not all kissing bugs carry the Trypanosoma cruzi parasite, and not every bite from an infected bug leads to transmission or illness.
Prevention and Control Measures
Protecting homes from kissing bugs involves several steps to limit their entry. Sealing cracks and gaps in walls, foundations, and around utility lines, and ensuring windows and doors have intact screens, prevents entry. Repairing holes in screens and keeping doors closed are also important. Turning off outdoor lights at night can reduce the attraction of flying adult bugs.
Maintaining a tidy outdoor environment around the house reduces potential habitats. This includes removing piles of wood, rocks, and brush, and clearing away wild animal nests or burrows. Pet owners should keep outdoor kennels clean and away from the house, and bring pets indoors at night to minimize exposure.
If a suspected kissing bug is found, do not touch it with bare hands. Instead, carefully collect it using a glove or small plastic bag and place it in a sealed container for identification. Professional pest control services can be considered for significant infestations.