Chagas Disease and Typhus in Texas

Believe or not in global warming as you will, but the Texas climate has changed and with it the geographic areas in which murine typhus (Rickettsia typhi) and Chagas disease (Trypanosoma cruzi) occur. Travis County just had its first ever typhus mortality, but the number of cases in Texas has been increasing as the disease has extended its range to the north in recent years. If infected fleas from rats and other animals bite a human, the human bite can be infected by the feces the insect leaves on the skin when the itching bite is scratched. YNN's recent report of a rat-infested home in central Austin and an inadequate number of city inspectors is discomfiting.

The geographic area in which Chagas occurs has extended northward into south Texas. Chagas is one of the neglected tropical diseases. It is unfamiliar to US doctors and is thus even less likely to be diagnosed in the early, readily treatable stage. Typically "kissing bugs" bite humans around the mouth and eyes and simultaneously leave their feces on the skin. The bites itch, and scratching infects the person with the trypanosome in the feces. The disease can also be transmitted from mother to child and by blood transfusion. Fleas from infected dogs and rats can also infect humans. There are life-threatening heart and gut problems in the late stage of the disease.

This University of Texas press release has a map of high-risk areas. Here is a picture of the bug and instructions on how to submit one for testing. Other names for the insect are triatomine bug, cone-nose bug, and vinchuca. It is called chinche in Spanish. The bugs submitted to the Texas state labs are being tested for the presence of the trypanosome. Bugs are also being gathered and tested for both Trypanosoma cruzi and the presence of human blood, meaning of course that an infected bug has bitten a human.