Hidden Threat: The Kissing Bug is spreading an exotic, bug-borne infection in Texas

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If she hadn’t gone to donate blood, Candace Stark wouldn’t have discovered that she harbored a dangerous parasite.

Although she hadn’t left Texas in 20 years, swimming in her blood was a tropical parasite that causes a disease called Chagas.

The parasite buries itself in heart muscle and the gut and can hide for two decades or more before causing symptoms, including sudden death.

Textbooks will tell you that Chagas disease, caused by the parasite Trypanosoma cruzi, is a problem for Central and South Americans living in poverty. Eight million to 11 million people are infected worldwide, according to the Pan American Health Organization.

But parasites care little about your bank balance, and although being poor is a risk factor for Chagas disease, the parasite is infecting Texans from all backgrounds.

Chagas is one of about 40 infections known as neglected tropical diseases, so-called because they are largely ignored by governments and drug companies. They infect 1.5 billion people in tropical and subtropical regions of the world.

But neglected tropical diseases are right at home in Texas. Rising temperatures, oblivious doctors and high poverty rates mean seven of these infections are already here or fighting to gain a foothold.

Experts warn that more cases of Chagas and other neglected tropical diseases are being reported in the U.S. An estimated 12 million Americans have one or more tropical infections, including an estimated 300,000 with Chagas disease.

In Texas, one in every 6,500 blood donors are infected with Chagas disease, compared with one in every 27,500 donors across the country.

Chances are, if you have it, you don’t know it. That’s because the parasite stays dormant for years and because American doctors are uneducated about the infection.

Chagas disease isn’t new to Texas, and neither is the dime-size kissing bug that spreads the infection. The first case in the U.S. was reported in 1955, and kissing bugs have been spotted in Texas since the early 1800s.

Kissing bugs live in rats’ nests and wood piles or in the nooks of your furniture or cracks in your house. They earned their name by biting us around our eyes and mouth. They poop where they eat, and when you rub the irritated bite, you rub the poop — and the parasite — into your skin. The infection is also spread through blood transfusions, organ transplants and, during pregnancy, from mother to baby.

Donating blood

At the blood donation center that summer afternoon in 2013, Candace’s pen hovered over check boxes for the question “Have you donated blood before?” What should she answer — yes or no?

She felt sure that she had given blood, but it had been such a long time and her memory was hazy. Better to say no, she thought. Just in case.

Because she answered no, the blood center tested her blood for antibodies to the parasite that causes Chagas disease. The next month, she received a certified letter from the blood center.

It said she had tested positive.

Candace had never heard of the disease. She didn’t even know how to pronounce it. She went online and typed “Chagas disease” into Google and found fact sheets and even videos. One in three people with the infection develop heart disease that can be deadly, she read.

A person can be infected for three decades or more without having any symptoms, said another website. She continued reading: When symptoms do start, they can include chest pain, difficulty breathing, tiredness and sudden death.

Her heart was racing. She called the U.S. Centers for Disease Control and Prevention. An adviser told her to contact an infectious disease doctor. She found one in College Station and, three days later, drove to her first appointment from her home in La Grange, a small town between Austin and Houston.

In the doctor’s office, Candace’s anxiety turned to anger. The doctor was an expert in infectious diseases but told her he didn’t know anything about Chagas disease. Find another doctor, he said.

The next doctor kept reading from books and looking through notes. Candace wanted to know when she would get medicine to kill the parasite. She had read that treatment could be 60 percent to 85 percent effective if taken soon after infection.

She didn’t know when she had been infected, only that she had tested positive a few weeks ago, but surely the sooner she got the medication the better.

The doctor told her that there was no approved treatment, only experimental drugs that are released by the CDC. CDC officials needed another blood test to prove she had Chagas before they would release the medication.

Six months later, Candace got the pills. She swallowed them twice a day for 60 days and went to a hospital for weekly blood tests to make sure the medication wasn’t damaging her insides.

Every two weeks, she drove an hour and a half to College Station to collect another batch of pills from the doctor. The CDC forbade the doctor from giving her more than a two-week supply.

Then 60 days was up and, just like that, the doctor said he didn’t need to see her again. No follow-up tests. No tests to see if the medication had worked. Just a goodbye.

Candace cried the whole drive home.

The impact on dogs

A four-hour drive north from her home in La Grange, Chagas disease was wreaking havoc on another family — in Plano. This time, it was Cora Fortin and Roy Nelson’s precious pooch who was afflicted.

Kiska is a Japanese spitz, which means she’s rare, expensive and adored by Cora and her husband, Roy. The couple had spent $700 just to fly her to Plano from a breeder in Sacramento, Calif. Perched on Cora’s lap, Kiska looks like a furry white pillow. But then black eyes open and a pink tongue emerges to remind you that this isn’t a pillow, it’s a dog.

Kiska’s fur is softest at the crown of her head. But move your hand a little lower, to the back of her neck, and you’ll feel a hard lump under soft skin.

It’s the pacemaker that was implanted four years ago to keep the little dog’s heart beating.

Until 2011, Kiska was happy and healthy, but her appetite for bugs landed her in big trouble. One day that September, she brought a strange-looking one into the house.

Roy jumped up and said, “What is that?” He tried to grab it, but Kiska pounced first and gobbled it up.

The heart attacks started the next week. Roy and Cora watched as Kiska stumbled and fell to the floor. She stood up, only to collapse 15 minutes later. Cora scooped Kiska into her arms and noticed that the dog’s heart was pounding double-time.

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Cora Fortin’s dog, Kiska, nearly died of heart failure after eating a kissing bug infected with the Chagas disease parasite. Today, a pacemaker implanted under Kiska’s soft fur keeps the little dog’s heart beating. (Smiley N. Pool/Staff Photographer)

And then it stopped.

They rushed to the Emergency Animal Hospital of Collin County, where two veterinarians watched Kiska collapse over and over. They said there was nothing they could do, that Kiska needed to be put down.

“Is she in pain?” said Cora.

“Probably, yes,” said the vets.

Then an older vet with thinning gray hair stepped into the room. He listened to Kiska’s heart, asked Cora some questions and said the dog could have Chagas disease.

Cora and Roy had never heard of the disease, but suddenly they had hope.

How big a problem? 

This vet wasn’t saying they should put Kiska out of her misery. He was saying they should get her to the Veterinary Medical Teaching Hospital at Texas A&M University, where a heart specialist could implant a pacemaker to keep Kiska’s heart beating.

The couple started driving toward College Station and Kiska kept fainting on the back seat. Cora propped her up on a stack of cushions and opened the window a few inches to let in fresh air. Kiska would have a heart attack every 15 minutes, and with each episode Cora and Roy would wonder: “Will she wake up this time?”

Nearly four hours later, they arrived at the hospital. A vet student met them at the entrance and took Kiska into the operating room. The vets told them to come back the next day.

Cora and Roy checked into a hotel and prayed for the best.

We don’t know if the incidence of Chagas is growing because, until very recently, nobody was counting.

Doctors and vets have to report some diseases to public health authorities, but in Texas, Chagas wasn’t one of those diseases until two years ago.

Since then, at least 39 people in the state have tested positive for the disease, according to the Texas Department of State Health Services. They say between 12 and 15 of those patients acquired the infection right here in Texas and not during travel to a tropical region.

Experts at the National School of Tropical Medicine in Houston worry that many more Texans are infected but don’t know it. They say doctors in Texas are not testing patients with heart failure for Chagas disease because very little is taught about neglected tropical diseases in medical schools.

That’s a problem not only for patients but also for anyone receiving a blood transfusion.

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Candace Stark stands in the closet at her father’s La Grange home, where she found a kissing bug. (Smiley N. Pool/Staff Photographer)

For patients, the problem is that, left untreated, a third of people with Chagas disease will suffer thickening of the cardiac muscle until the heart becomes a pathetic, weak pump and the body is deprived of blood. One in 10 will suffer damage to the nerves and gut so that food sticks in the bowels until patients can no longer defecate.

The problem for anyone receiving a blood transfusion is that current guidelines require donors to be tested for the parasite only once in a lifetime.

In 2007, blood centers started to voluntarily screen first-time donors. More than 2,000 people have tested positive since then.

Among them are Texans who received letters from blood centers saying their blood could not be accepted because they were infected with a tropical disease. When they took the letter to their family doctor, they were told that there must be some mix-up, that Chagas disease didn’t occur in the U.S.

At the National School of Tropical Medicine, Dr. Kristy Murray, a vet and Chagas disease expert, offers eight-week courses on tropical diseases for doctors who have an interest.

But it’s not enough, she says. Every doctor in Texas should learn about Chagas and should understand that it’s a local disease.

Would the pills work?

Candace wiped the tears from her face and pulled up outside her house. She had done her part — researched the disease and taken the pills exactly as her doctor had said.

Now she didn’t know if any of it had worked.

But she was a practical woman. She doubled her life insurance and told her three children how they should divide her estate when she died.

So far, she had no symptoms, but every twinge felt like a possible sign of Chagas disease. Was she tired because her day was long, or was the parasite starting to attack? At night, the creepy video of the parasite wriggling through human blood played over and over in her mind.

If she was anxious through the night, she was filled with shame during the day.

When Candace asked her doctor if she should tell her neighbors about her disease so they could be on the lookout for kissing bugs, the doctor asked if she knew about Typhoid Mary.

“If you want to be her, go ahead and tell anyone you want,” he said.

Candace didn’t know who Typhoid Mary was, but she understood the doctor’s message: Keep your mouth shut. And so she did. She didn’t tell her neighbors or anyone who might be at risk.

Typhoid Mary, whose real name was Mary Mallon, was an Irish cook in New York in the early 1900s. She carried a type of bacteria that could be spread through food prepared by an infected person, even if that person wasn’t showing symptoms.

Mary went against the advice of public health officials by working as a cook while infectious. She infected 51 people and was quarantined on an island, where she died after 23 years in isolation.

Mary carried a disease that could be spread from person to person. Candace posed no such risk (unless she donated blood). Her doctor’s advice didn’t make sense, so she searched for someone who could give her real answers.

She found two vets at Texas A&M University. The vets gave her more information about Chagas disease than any doctor she’d met.

Vets know more

Murray, the vet at the National School of Tropical Medicine, was giving a talk about Chagas disease to 200 vets.

“Hands up if you’ve ever diagnosed a case of Chagas,” she said. Nearly 200 hands went up. A few weeks later, she gave the same talk to a group of doctors and asked the same question. None of the doctors raised their hands.

The disconnect between doctors and vets was obvious.

Back when our livelihoods depended on animals, vets were revered. It wasn’t unusual for a farmer to call a vet to tend to his injured cattle and set his own broken arm.

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Ph.D. student Carolyn Hodo conducts a test on a kissing bug while working with Dr. Sarah Hamer at Texas A&M University’s College of Veterinary Medicine. (Smiley N. Pool/Staff Photographer)

But then the industrial revolution happened. Doctors gained a God-like status while the importance of vets and animals dwindled.

A chasm between the professions grew, and although many vets read medical journals about human diseases, doctors rarely read about animal health, even though three of every five new human diseases is spread from animals.

If doctors did read up on animal health, they would learn about epidemics that hold important clues for us.

The recent Ebola outbreak was probably sparked by a child playing with an infected bat. An outbreak of chlamydia in koala bears offers the chance to learn more about how that infection spreads. An obesity epidemic in dragonflies with a gut parasite can teach us how infections are linked to weight gain.

At Lackland Air Force Base in San Antonio, 70 military working dogs since 2006 have been infected with the parasite that causes Chagas disease. The dogs, which cost $20,000 to $30,000 to train, play a critical role in detecting explosives and preventing injury to their human teammates. But when their hearts weaken from Chagas disease, they are either retired or put down.

Chagas disease isn’t spread from dogs to humans, but infection in animals can serve as an early-warning sign for us. In Texas, most vets know that almost 10 percent of dogs in the state carry the parasite that causes Chagas disease.

That discovery was made by Dr. Sarah Hamer, one of the vets at Texas A&M University who talked to Candace. Hamer heads up a lab that receives kissing bugs sent in from all over the state.

Hamer chops the bugs’ heads off and tests them for the parasite and for human blood. Sixty percent of bugs test positive for the parasite and 66 percent test positive for human blood. If the bugs are caught inside someone’s house, as opposed to outdoors, nearly 100 percent test positive for human blood.

That means the kissing bugs are infected and they’re biting humans.

Living with Chagas

Cora and Roy, who now live in Fairview, Texas, took turns holding Kiska. She was wrapped in blue bandages, still drowsy from surgery, and the pacemaker was keeping her heart beating. They looked at the hospital bills and gave Kiska a new nickname — the $10,000 dog.

When they arrived back in Plano, she bounded into the house and landed on her favorite spot on the sofa as if nothing had happened.

Four pills that Cora smears with peanut butter every day and an annual pacemaker check are the only reminders that Kiska’s heart is oversized and weak.

But when she is breathless or maybe just lazy, Cora and Roy wonder if the parasite inside her is multiplying.

Candace wonders the same thing about herself. She lives with a 1 in 3 chance that her heart will get bigger and weaker and eventually stop working. For now, there are no symptoms, but she thinks about how long she has before the parasite wakes up.

[This story was originally published by The Dallas Morning News.]