The Centers for Disease Control has changed its thinking about so-called “Kissing Bugs” and the Chagas disease they carry, according to a bulletin on emerging infectious diseases published Sept. 9. (Vol. 31, No. 9)
Researchers now say kissing bugs, which are triatomine insects, should be considered endemic in the United States, with significant populations established throughout the south, especially in Texas, where seven of the 11 species found in North America can be found.
Chagas disease, caused by Trypanosoma cruzi parasites, has been known in South America since 1902, and has spread north and south, most recently considered endemic in 21 countries, excluding the U.S.
However, new evidence shows domestic animals, wildlife, and humans are increasingly being infected by the parasite.
The report states that pets — especially dogs — are increasingly at risk in the region.
Autochthonous human cases — cases where the pathogen came from bugs in established populations — have been reported in eight states, including Texas.
Researchers have recommended labeling the Chagas disease in the U.S. as “hypoendemic,” meaning its is constantly present at low levels, and they urged improvements to surveillance, research and public health responses.
How Chagas Disease Spreads
According to doctors, when an infected triatomine insect — or “kissing” bug — takes a blood meal, it also releases a parasite in its feces near the bite wound.
The T. cruzi parasite enters a host through the bite wound or contact with mucous membranes.
Apart from humans, a number of mammals serve as reservoir hosts for T. cruzi, including armadillos, opossums, raccoons, rodents, woodrats, and especially domestic dogs.
Chagas disease, first identified by Dr. Chagas in Brazil in 1902, has become endemic in a zone including much of the continental U.S., south to Argentina.
According to information from the CDC, the disease has two distinct phases with different symptoms.
During the Acute Phase (2-8 weeks after infection)many infected persons are asymptomatic, with 50-70 percent of cases reporting little or no symptoms.
However, about one-half to one-third of those infected experience body aches, headaches, swollen lymph nodes and eyelids, fever, fatigue, rashes, vomiting and diarrhea.
Because the disease is often undetected for extended periods, the Chronic Phase includes long-term damage like heart disease, neurological problems and digestive issues, along with chest pain, shortness of breath, joint pains and muscle weakness.
Dealing With the Problem
Research conducted by the Canine Health Foundation used trained detection dogs to locate kissing bugs at multiple sites across Texas in the fall of 2017. Dogs are very good at finding these bugs by smell.
Testing of the bugs they collected revealed that 27 percent of immature specimens were infected with T. cruzi. Researcher also found the bugs had been feeding primarily on woodrats, opossums, and rabbits.
Experts suggest protecting pets by keeping them indoors, especially at night and reducing attractive features like wood, brush or rock piles.
The insects are also attracted to outdoor lighting.
Other tips include:
- Seal up any gaps in the exterior your home
- Find pet-safe insecticides to use in backyards and around kennels
- Prevent dogs from investigating beetles and other insects, or interacting with wildlife.
According to experts, pyrethrin/permethrin-based insecticides can be applied to outdoor kennels and areas where your pet spends time, but be cautious if you have cats, because high concentrations of these products are toxic to cats.
For more information on Chagas disease, please visit www.cdc.gov/parasites/chagas and click “General
Information,“ or call 404-718-4745.
