Chagas disease, a parasitic infection spread to humans by insects, is not the new HIV/AIDS of the Americas, according to infectious disease experts who called the comparison “unrealistic” and “unfortunate.”
Responding to an editorial posted Monday in PLoS Neglected Tropical Diseases and the media attention that followed, Rick Tarleton, president of the Chagas Disease Foundation, said the diseases have little in common beyond disproportionately affecting poor people.
“I think it’s an unfortunate comparison,” said Tarleton, a distinguished research professor at the University of Georgia studying Chagas disease. “There are stigmas attached to HIV/AIDS that themselves are inappropriate, but it would be even more inappropriate to apply them to something like Chagas disease.”
About 300,000 people in the U.S. have Chagas disease, an infection transmitted to humans by blood-sucking insects. But almost all of them became infected before coming to the U.S. from Mexico, Central America and South America, where roughly 10 million people have the disease.
“It’s difficult to say whether the type of attention this is generating is going to be good or bad for people with the disease,” said Tarleton, describing how many people with Chagas disease face obstacles in getting care. “I don’t think the comparison to HIVAIDS is a realistic one, and I don’t expect it to serve the situation terribly well.”
But Dr. Peter Hotez, dean of Baylor College of Medicine’s National School of Tropical Medicine, said he penned the provocative editorial to rally resources for people with Chagas disease.
“I wanted to call attention to the disease; make people aware of it,” said Hotez, adding he had no intention to diminish the impact of HIV/AIDS. “I believe that Chagas disease is every bit as important as the AIDS problem, but no one’s ever heard of the disease.”
When asked whether drawing a connection to HIV would stigmatize people with Chagas disease, Hotez replied “I don’t think it can get any worse for them.”
“They already lack access to medical care and many governments are ignoring the problem,” he said. “They’re already treated as outcasts.”
The insects that transmit Chagas disease, nicknamed “kissing bugs” for their tendency to bite people’s lips, infest low-income housing in countries where the disease is endemic. They bite at night, allowing parasites from their feces to infect the itchy wound. Insecticide can kill them, but few can afford it.
“For most of the people affected, it’s not an avoidable infection,” said Tarleton. “It is totally preventable, but largely unavoidable in certain regions.”
But unlike HIV, Chagas disease is largely asymptomatic. Only 30 percent of those who get it develop serious health problems such as heart failure.
“An HIV infection without treatment is essentially a death sentence, but most people with Chagas disease live with the infection for many decades and some people live a perfectly long life without any treatment,” said Tarleton.
And unlike HIV, Chagas disease can be treated in three months.
“In Chagas disease, there are treatments that cure the infection,” said Tarleton. Current HIV treatments are life-long. “The downside is there is toxicity associated with those drugs in a substantial number of people, and it’s difficult to determine how effective the drugs are. They can cure the infection, but they don’t always cure the infection.”
Those drugs also come at a cost upward of $11,000, according to the editorial, making them out of reach for most.
Dr. William Schaffner, chair of preventive medicine at Vanderbilt University Medical Center in Nashville, Tenn., and president of the National Foundation for Infectious Diseases, agreed there’s much to be done to improve care for people with Chagas disease.
“This might be called a forgotten disease of forgotten people — impoverished people in the developing world. And there have not been major efforts to find better drugs to combat this illness,” he said.
And while the comparison between Chagas and HIV may be alarmist, Schaffner said he hopes it will help rally resources.
“I was surprised, frankly, at the whole tone of the editorial,” he said. “But I hope it shifts the view from forgotten problems of forgotten people to newly recognized and appreciated problems of people who need help.”