Wednesday, December 2, 2015

Kissing Bugs and Chagas Disease in North Carolina

By now, you’ve probably heard news reports out of Texas and now North Carolina, about a "deadly" insect, the kissing bug. The bug is native to the southern United States, South America, Central America and Mexico, and can carry a parasite Trypanosoma cruzi that causes Chagas disease.

The Eastern blood-sucking conenose (AKA kissing bug),
Triatoma sanguisuga, is native to NC and much of the 
southern and middle U.S.
Kissing bugs tend to bite sleeping people on the thin skin near their eyes or mouths, hence the nickname. Unfortunately, the bugs also defecate at the site of the bite. These feces can enter the wound when a person scratches or rubs their face, and if the bug was infected T. cruzi, infection with Chagas disease can follow.

There are at least two species of kissing bugs that are native to North Carolina: Triatoma sanguisuga and T. lecticularia. But before you panic, it’s important to know that most cases of Chagas disease are actually from rural areas in the New World tropics. Cases of Chagas disease in the United States are rare; most cases of Chagas disease have been diagnosed from people who traveled here from outside the country. In fact, since 1955, only seven verified cases of native-infected Chagas have been reported in in the United States, and none of those occurred in North Carolina. One reason they are not frequently encountered is because kissing bugs are nocturnal and prefer to hide during the day.

There are many other insects in North Carolina that look similar and can be mistaken for kissing bugs. Kissing bugs belong in the family Reduviidae. Other bugs in this family are similar in appearance, but they feed on plants and other insects and can inflict a painful bite when disturbed. However, only kissing bugs are known to transmit the Chagas parasite. Kissing bugs feed on a diversity of wild and domestic animals including wild rodents, other wild mammals, domestic dogs, and humans. You can find some common insects that are mistaken for kissing bugs by visiting the NCSU Plant Disease and Insect Clinic blog.

So, what exactly do kissing bugs look like? Kissing bugs are around one inch in length when fully grown and somewhat flattened. The sides of their abdomen and thorax are striped, alternating black and orange/red. (see photo above). The legs of kissing bugs are thin compared to most assassin bugs. The front of the head is elongate and the mouthpart is long and thin. They also have a prominent spine on the back of the thorax. 

To reduce the chance of kissing bugs entering the home, work on excluding them. Some of the following may help to seal the home to keep the bugs outside:
  • Cut back trees and shrubs so they do not touch or overhang the house
  • Don’t stack firewood or other items directly against the house
  • Install weather stripping around loose fitting doors and windows.
  • Seal cracks and gaps in the foundation with caulk
  • Close up weep holes with copper mesh
  • Use stainless steel mesh wire to block larger access points in the attic
  • Make sure window screens aren’t torn or ripped 
  • Turn off outside lights at night. If that is not possible, use “bug bulbs” or try LED bulbs that have a wavelength less attractive to insects
If you think you’ve encountered a kissing bug, trap the bug in a container without touching it. Fill the container with rubbing alcohol or freeze the bug. Take the bug to your county cooperative extension center, health department or university lab for proper identification.