‘Kissing bug’ disease is here to stay in the U.S., experts say. Here’s why it’s spreading

Chagas largely spreads when triatomine bugs, commonly known as kissing bugs, bite a human while they’re sleeping. (Universal Images Group/Getty Images via CNN Newsource)

Chagas disease, a potentially deadly condition caused by a parasite carried by insects called kissing bugs, should now be considered endemic in the United States, experts say – and without recognition that it’s a constant presence in some parts of the country, more people will suffer unnecessarily.

A report on the topic was published last week in the U.S. Centers for Disease Control and Prevention’s journal Emerging Infectious Diseases, and the authors say they hope that growing global attention on the new paper means Chagas could finally get the surveillance, prevention and testing efforts and research funding it deserves in the United States.

“We’ve been waiting forever; all of us Chagas people have been waiting for people to recognize this disease is in our communities,” said Dr. Norman Beatty, coauthor of the report and a clinical associate professor at the University of Florida College of Medicine’s Division of Infectious Diseases & Global Medicine who has studied Chagas for the past decade.

The World Health Organization considers Chagas a neglected tropical disease, and the Pan American Health Organization says it is endemic – with a constant presence or usual prevalence – in 21 other countries in the Americas, not including the United States. Chagas is one of the leading causes of heart disease in Latin America, and it causes more disability than other insect-borne infections, even more than malaria and Zika, studies show.

Chagas largely spreads when triatomine bugs, commonly known as kissing bugs, bite a human while they’re sleeping. The bug defecates in that bite or on a person’s face, and the person unwittingly wipes the feces into their eyes, nose or mouth. The feces can carry a parasite, Trypanosoma cruzi, that causes the disease.

Chagas can also spread through contaminated food or blood, organ transplants and pregnancy.

Early symptoms can include fever, body aches, headaches, rash, vomiting and tiredness. They may last weeks or even months after initial infection.

According to the CDC, about 20 per cent to 30 per cent of people who’ve been infected develop more serious problems like long-term digestive and nervous system conditions, heart failure, stroke or death.

If it’s caught early, the disease can be cured with benznidazole or nifurtimox, medicines that kill the parasite. But the drugs become less effective the longer a person has been infected, and most people remain unaware of the disease. Many doctors don’t think to look for it in patients in the U.S., the new report noted.

In fact, some people who are infected find out some time later, when they donate blood, since the U.S. has been testing its blood supply for Chagas since 2007.

Surveillance is limited, but the CDC estimates that about 280,000 people in the U.S. have Chagas at any given time. It’s unclear how many have the more serious form of the disease or how many deaths are caused by Chagas each year.

Scientists have found kissing bugs in 32 states, the new report says. The blood-sucking insect mostly lives in warmer Southern states, but with climate change causing more bug-friendly temperatures, there’s a good chance they have spread farther.

Scientistst have identified at least 17 states with infected mammals, including Virginia opossums, raccoons, banded armadillos, striped skunks, coyotes and wood rats, according to the latest report. Veterinarians have seen infections in zoo animals and pets, including cats, dogs and a horse.

Doctors have reported Chagas cases in humans in eight states: Arkansas, Arizona, California, Louisiana, Missouri, Mississippi, Tennessee and Texas. There are probably more cases, the new report says, but doctors are not required to report Chagas infections in most states.

It would be “momentous” for Chagas to be declared endemic in the U.S., said Dr. Mario J. Grijalva, director of the Infectious and Tropical Disease Institute and professor in the Department of Biomedical Sciences at Ohio University.

“When you consider it a problem that belongs to others, it’s not important. But when it’s a problem affecting people here, the recognition that it is an endemic disease in the United States is a game-changer, at least in terms of the public policy possibilities and the awareness that is required to properly address this complicated issue,” he said.

Grijalva knows firsthand what a difference it can make to have awareness and a concerted health campaign. He spent his recent sabbatical riding a motorcycle across Latin America to spread the word about the condition, after making a similar motorcycle trip in the US.

In countries like Ecuador and Peru where Chagas is endemic but there is no concerted government efforts to manage it, most people were unaware of the disease, Grijalva said. But in Chile, Bolivia and Argentina - all countries with robust health and public awareness campaigns – the people he spoke with knew about Chagas, and many cases were being well-managed.

“There has been a lot of effort to fight this in those countries,” Grijalva said. “It can be fought, and there are a lot of successes.”

Beatty hopes broader recognition of Chagas in the U.S. will prompt officials to step up surveillance efforts like what he’s seen in some other countries. He also hopes health care providers learn to recognize cases sooner and wishes the US would work to protect people from kissing bugs like it does mosquitoes.

“We have mosquito control programs around the country, but we’re essentially doing nothing about kissing bugs,” he said.

In the meantime, he said, people aiming to keep the insects away can better seal their homes, use window screens and spray for bugs. However, he has not found any particular spray specifically approved to target kissing bugs in the U.S.

And in Florida, where he works and where about 30 per cent of kissing bugs seem to be positive for the parasites, Beatty said, people will often send him bug photos or even drop the insects off at his hospital to be tested.

“They’re scared,” he said – and they have a right to be.

Beatty said he tries to help his community as best he can. “There’s not another doctor around here walking around with bugs in their pockets,” he said. But with more awareness, he hopes others will step up as well.

“I’m just one person,” Beatty said. “It’s a small team, and we have limited resources.”

By Jen Christensen, CNN