Like killer bees, the insects that transmits Chagas disease have crossed the Mexican border into the southern United States. The University of Texas at Austin online newspage reported on October 6, 2011, that south Texas is at high risk for the infection, which is endemic in rural areas of Latin America.
Chagas disease is caused by the protozoan Trypanosoma cruzi, and spread by insects of the Triatoma genus, called triatomine bugs or “kissing bugs”.
Sahotra Sarkar of the University of Texas and colleagues in Texas and Mexico provided a report on Chagas disease. A lower estimate for the number of cases in the entire United States is 300,167.
Most of these are in immigrants, who may have been infected outside the United States. However, cases of human infection have been confirmed as originating in Texas, California, Louisiana and Tennessee.
The symptoms are similar to flu symptoms, so many more cases may go undiagnosed. The pathogen lives in the body for decades after the symptoms appear to clear up, and may cause life-threatening heart or digestive disorders later in life.
The Centers for Disease Control and Prevention website explains that triatomine bugs usually live outside, but may be found indoors near pet resting areas, in areas of rodent infestation, and in bedrooms. They live on the blood of humans and other animals, feeding at night while the host is asleep.
The Trypanosoma cruzi parasites are transmitted through insect feces. Allergic reactions to the triatomine bug bites may also occur.
In addition to transmission from insects, Chagas disease can sometimes be spread directly from human to human. Infected mothers can transmit the disease to their babies. Blood transfusions, organ transplants, lab accidents, and contaminated foods also pose a risk of infection.
Sarkar and colleagues noted that only Arizona and Massachusetts require doctors to report Chagas disease.