Kiss of Death

Kissing bugs aren’t new. They aren’t an invasive species; they’ve always been here; they are part of the family that contains assassin bugs, and there are 10 species of kissing bugs present in the United States (plus one very rare species). They are sometimes called Triatoma bugs because they are in the subfamily Triatominae and the genus Triatoma. Like all assassin bugs, these are predators that use their piercing-sucking mouthparts to pierce the skin and suck up the blood. Nymphs and adults, males and females, feed on blood. They feed mostly on vertebrate blood.

Much like bed bugs, these tend to hide during the day in dark, sheltered spots and come out at night to bite their unsuspecting prey. They are attracted to carbon dioxide, heat and other body smells. Kissing bugs get their name because they tend to bite near the mouth and other areas of the face that are easily accessible, thus, “kissing” their victims. Also, like bed bugs, they will feed multiple times.

FUN FACT

THE DISEASE. Chagas disease is caused by the protozoan parasite Trypanosoma cruizi. The World Health Organization (WHO) estimates more than 7 million people, mostly in Latin America, are infected.³ There are an estimated 10,000 deaths each year. The disease is named after the Brazilian physician Carlos Chagas, who diagnosed it in 1909.

The parasite is in the feces of the kissing bug. It is not in their saliva or their “bite.” After they “kiss” their prey, sometime during the process, they defecate. A sleeping person swipes at the annoyance and wipes some of the feces with the parasite into the bite wound.

Scientists have found that about 50% of kissing bugs are infected with the Chagas parasite.⁴ They often bite around the face and it’s easy to wipe the contaminated feces into the eyes or other mucus membranes.

FUN FACT

THE SYMPTOMS. There is an acute and chronic phase to the disease. The acute phase is for about two months as the parasite starts replicating and building up in the body. Symptoms are typically flu-like, with fever, headache, muscle pain and sometimes difficulty breathing. When caught early, antiparasitic treatments are very effective at eliminating the disease.

The chronic phase is when the parasites have invaded the heart and/or digestive system. This can take decades. Ten to 30 years after the initial infection, symptoms are much more severe. They can include damage to the nervous system and heart muscles. This leads to cardiac arrhythmia, progressive heart failure, and sudden death. Some can develop severe digestive issues.

THE LOCATION. The T. cruzi parasite is found throughout the Americas. In the U.S., it has been noted from coast to coast, in the southern half of the country. As of 2022, Chagas disease was only reportable in seven states (Arizona, Arkansas, Louisiana, Mississippi, Tennessee, Texas and Utah⁶). It is likely in many more areas. Research shows low levels of Chagas (up to 0.7% of the population) in most major U.S., cities.⁷ Approximately 240,000 to 350,000 persons living in the U.S. are infected. It can be found in dogs and many other wild vertebrates, including opossum, raccoon and rodents.

SHOULD YOU WORRY? The short answer is no. Early on, Carlos Chagas recognized the potential benefits of improved housing to prevent triatomine infestation. If kissing bugs aren’t inside the structure, people are less likely to get bitten at night. While they do aggregate like bed bugs, they are much bigger (as adults at least), so they are more noticeable and more likely to be removed when seen. Also, since T. cruzi is transmitted to humans through the feces of the bugs, the species in the U.S. has more of a delayed defecation and movement away from the host compared to the South American kissing bug, T. infestans.

In the U.S., transmission from an infected kissing bug to a human host is rare. The major concern is anaphylactic reactions to their bites.⁸

SHOULD WE DO SOMETHING? Absolutely. In areas where kissing bugs are common, they can be treated much like any other accidental or seasonal invader. Excluding them from structures is the best option, but we know it’s impossible to seal up every crack and crevice where these (or other insects) can get in. Sanitation also helps. Since these feed on many small mammals, reducing the conducive conditions that attract mammals reduces the kissing bugs.

Treatments can be made similar to how they would be made for other invaders. Focusing on cracks, crevices, door seals and other entry points with a labeled product can put up another barrier to entry. Full perimeter treatments are typically not necessary. Of course, it is essential to communicate with the customer about their role in exclusion and sanitation as well.

Because kissing bugs have been in the news lately, and likely will be in the in future years, customers will be concerned. Don’t forget to correctly identify the pest. Customers can think that anything is a kissing bug! Be prepared with information pieces and proper treatment protocols. As always, refer people to a medical professional if there are concerns over bites. Finally, protect yourself with proper PPE and the right knowledge to do the job and prevent the dreaded callback!

The author is consulting entomologist at 360 Pest and Food Safety Consulting.

References

1 https://pmc.ncbi.nlm.nih.gov/articles/PMC 4264683/

2 https://www.scielo.br/j/mioc/a/hnTFZMqqb 5RDwnJmXbKcTpr/?lang=en

3 https://www.who.int/news-room/fact-sheets/ detail/chagas-disease-(american-trypanosomiasis)

4 https://kissingbug.tamu.edu/

5 https://repositorio.uchile.cl/xmlui/bitstream/handle/2250/118759/Botto_Mahan_Carezza.pdf?sequence=1

6 https://pmc.ncbi.nlm.nih.gov/articles/PMC 10442057/pdf/nihms-1895762.pdf

7 https://pmc.ncbi.nlm.nih.gov/articles/PMC 9239882/pdf/21-2221.pdf

8 https://academic.oup.com/cid/article-abstract /50/12/1629/304928?redirectedFrom=fulltext

9 https://www.nature.com/articles/nature 09220.pdf