Doctors think ‘exotic’ tropical illness underreported in Valley, Texas

HARLINGEN — The curious case was discovered, as it often is, when the person decided to donate blood.

The fit, 18-year-old U.S. Air Force trainee at Joint Base San Antonio was given a blood test like all people who donate blood for the first time.

It turned up positive to antibodies for Chagas disease, a potentially fatal parasitical illness transmitted by an insect called the kissing bug.

Chagas is common in Central and South American, and most cases diagnosed to date in the United States involve people who have lived in that area of the world, or visited for a significant amount of time.

But our Air Force enlistee, a Texas resident, had no such travel history. He was infected with Chagas right here.

Chagas, the world and Texas

Worldwide, there are anywhere between 5 million and 8 million people infected with the parasite Trypanosoma cruzi, the protozoan that causes Chagas disease.

In the United States, there have been about 240,000 Chagas cases, nearly all of which were linked to Latin America or South America. Fewer than 30 locally acquired cases have been recorded.

Between 2013 and 2015, Texas Department of State Health Services’ data show 64 cases of Chagas disease were diagnosed in the state. Of those, 15 were definitively determined to have been locally acquired, 44 cases were imported from Central America or South America and five cases were of undetermined origin.