Excerpts from Jim Conrad's
Naturalist Newsletter

from the June 11, 2017 Newsletter issued from Rancho Regensis north of Valladolid, Yucatán, MÉXICO
KISSING-BUGS AND CHAGAS DISEASE
Sometimes on the walls of little family stores, doctors' offices and public buildings in this area you see a blown-up picture of a Triatomine Bug, sometimes known as a Kissing Bug. That explains why when the other day a Kissing Bug showed up on the hut's floor, I recognized him. I'd been waiting for him, and you can meet him below:

Kissing Bug, TRIATOMA DIMIDIATA

That's TRIATOMA DIMIDIATA, one of several species of "Triatomine Bug." Triatoma dimidiata is distributed from central Mexico south through all of Central America into northern South America. The reason Kissing Bug pictures are posted in so many public places around here is that they spread Chagas Disease, which is a problem in the Yucatan. In the warmer US states, Chagas Disease also is spread by bugs of this genus, but not by our species. In the US eleven different species of kissing bugs have been documented. Over half the Kissing Bugs submitted to researchers in Texas were found to be infected with the Chagus Disease parasite.

Chagas Disease can kill by causing heart failure, but it takes years to develop to its final stages. For years during the disease's early phases the patient suffers vague, hard-to-diagnose symptoms often shared with many other diseases, including fever, headache, enlarged lymph glands, muscle pain, etc. More information on its signs and symptoms are provided on a World Health Organization page at http://www.who.int/mediacentre/factsheets/fs340/en/

That page tells us that Chagas Disease affects 6-7,000,000 people worldwide, mostly in Latin America. Triatomine Bugs like our Triatoma dimidiata carry the microscopic parasite Trypanosoma cruzi, which causes the disease. A 2007 study by Guzman-Tapia and others found our Triatoma dimidiata Kissing Bug to be fairly common in the Yucatan's capital city Mérida, and surrounding villages. Nearly half the bugs collected for that study carried the Chagas Disease organism.

The bugs, which normally are active at night, usually bite exposed skin, and then defecate close to the bite. The parasites enter the body when the person unthinkingly smears the bug's feces or urine into the bite, the eyes, the mouth, or any break in the skin.

The disease is easily treated with almost 100% recovery, if attended to soon after the infection. However, its vague symptoms are so hard to diagnose that often infected people suffer for years, and maybe die, without knowing what they have.

I always sleep beneath a mosquito net, but sometimes I awaken to find that in the night an elbow, foot or my butt has been pressed against the net's side, where an itching sore has developed. The Kissing Bug is always the first thing I think of then. However, I'm hoping that the net keeps the Kissing Bugs from pooping onto my skin, and it's the poop that's the main problem, not the bite.