Chagas disease and Kissing Bugs

Photo of kissing bug

Triatoma protracta, above, is the “kissing bug” most commonly found in Colorado.
What is Chagas disease?

Chagas disease is caused by a single-celled parasite, Trypanosoma cruzi and is most commonly spread in Mexico, Central and South America. Local spread may occur in the U.S., but it is not common.

Chagas disease has two phases. The acute phase usually goes unnoticed because most people have no symptoms or only have a mild illness that occurs 1-2 weeks after exposure. Sometimes, the only sign of exposure is a swollen eyelid on one side of the face where the bug bit. The chronic phase can occur in a small number of people years to decades after exposure. Chronic Chagas disease may result in severe illness.

How does Chagas disease spread?

  • Blood-feeding insects called triatomine bugs (kissing bugs) are the most common way Chagas disease spreads. The parasite lives in the bug’s gut and is spread through its feces (poop). The bug bites, then defecates (poops), and the parasite enters a bite wound, eyes, nose or mouth.  Some species of kissing bugs spread the disease more easily. For example, the South American species usually defecate right after feeding, while still on the person. This increases the risk of disease.
  • The parasite also can be spread from eating food or beverages contaminated with bug feces, eating uncooked meats from infected animals, from mother-to-baby, through blood products, or by eating the bugs.
  • Dogs commonly eat the “kissing bugs” and are at higher risk of infection.
Does Colorado have kissing bugs or Chagas disease?
  • Colorado does have kissing bugs. They are nesting bugs, typically associated with rodent nests. The most common species in our state is Triatoma protracta.
  • Colorado’s common kissing bug is capable of spreading Chagas disease but is not very good at it. That’s because the bug usually defecates after it is off the person.
  • If you or your pets may have been bitten by a kissing bug, call your healthcare provider or veterinarian.
  • Health care providers or veterinarians who have questions about testing patients for Chagas disease can call the state health department
    at 303-692-2700.
Colorado kissing bug study
  • The state health department is working to determine the distribution of kissing bugs and if there are other species in Colorado.
  • If you find an insect that looks like a kissing bug, please review the "Conenose Bugs (“Kissing Bugs”) and Insects of Similar Appearance in Colorado" Fact Sheet by W.S. Cranshaw
  • ​​While the insect is safely contained in a glass jar or similar container and after putting on gloves, use a magnifier/light app on your phone or a magnifying glass to examine the shape of the insect's head, beak (proboscis) shape and length, back-leg shape, coloring, and note the location the insect was found. 
  • If after reviewing the document and the pictures of kissing bug look-alike insects commonly found in Colorado, your insect is determined to be a look-alike and not a true kissing bug (Conenose bug/Triatoma genus in Colorado) you may safely release or discard the insect. Be careful as some of the look-alike insects will bite when provoked. Only the true kissing bugs (Conenose bugs/Triatoma genus in Colorado) can potentially transmit the parasite that causes Chagas disease and should be saved for identification and possible testing.
  • If the insect you found was not easily ruled out as a true kissing bug (Conenose bugs/Triatoma genus in Colorado) please 
  • Use this form to submit it for identification, or call the department at 303-692-2700.