Chagas, which afflicts millions in Latin America, was long thought to be largely confined there. But a recently approved test to screen blood donors has identified hundreds of cases across the United States–including eight in Bexar County.
The sudden appearance of these cases has taken some health officials by surprise. And although many of these patients may prove to be immigrants who brought the disease into the United States–or their children, since it can be passed from mother to child–experts believe some were infected in this country.
With new information from the blood banks, they hope to get a better idea of how many. Few here ever are tested for Chagas (pronounced SHAH-gus), even those diagnosed with the classic symptoms.
Area health officials have begun the job of tracking down donors who tested positive to interview them about their travel histories and risk factors. A federal investigation is similarly under way nationwide.
“Here at CDC, we’re trying to identify how people are getting infected in the U.S.,” said Dr. Susan Montgomery with the parasitic diseases branch of the Centers for Disease Control and Prevention. “Are there activities they are engaging in where they come in contact with infected wildlife or the infected bugs (through) camping or hunting?”
E.J. Hanford, professor of environmental science at Collin County Community College in Frisco who has co-authored papers on Chagas, estimates that perhaps 200,000 immigrants in the United States could have chronic Chagas disease–most of them likely unaware–based on known infection rates and patterns throughout the hemisphere.
“Physicians in general–other than a few–never even think about this disease,” Southern [Dr. Paul Southern, professor of pathology at UT Southwestern Medical Center in Dallas, who has studied Chagas in Belize] said. “It’s not a part of their consciousness. They could see a kid with a swollen eye who said a bug bit him and not think about Chagas disease. That’s one of the main impediments to recognition.”