Chagas disease, also known as "kissing bug disease," isn't well-known in the United States, but it's been around for thousands of years. The bug doesn't really kiss you, but it may give you a little harmless bite near your mouth.
And if you rub your face or eye near the bite and the bug is infected with a parasite called Trypanosoma cruzi (T. cruzi), you may get Chagas disease. The disease infects up to 8 million people, mostly in Latin America.
The bugs live in the Southern and Western parts of the U.S., but only half the bugs carry the parasite. The CDC estimates that about 300,000 people in the U.S. have Chagas disease.
Although most people were likely infected in Latin America, Chagas disease is endemic in the U.S. because it's always present at low levels.
How Do You Get Chagas Disease?
T. cruzi isn't passed from person to person like a cold or the flu. Instead, the parasite spreads by triatomine bugs, also known as "kissing bugs."
They’re called that because they bite you on the thin skin around your eyes or mouth, usually while you are asleep. The bites are fairly painless and probably wouldn't wake you up.
But the bug's bite isn't what causes the infection – it's their poop. If a bug bites an infected animal or person, they become a carrier of T. cruzi, which is passed through feces.
The next time the bug feeds on a person, it leaves droppings on them, which can enter that person's body through their:
- Eyes
- Nose
- Mouth
- The bug bite or wound
Other ways to get infected
Although people mainly get infected from triatomine bugs, the parasite can be passed a few other ways:
- A blood transfusion or organ transplant from an infected person
- Eating uncooked food that's been contaminated with the parasite
- Eating undercooked meat from an infected animal
- An infected pregnant person can transmit the disease to a baby in the womb.
One study from the University of Pennsylvania School of Medicine found that bedbugs can carry T. cruzi. It's not clear whether these bugs are likely to pass the parasite to people, though.
What Are the Symptoms of Chagas Disease?
Chagas disease has two phases. The first phase can last a few months after you've been bitten. Most people don't get symptoms, and it can be hard to tell if you're infected. Only 1 out of 3 people get the chronic form (the second phase) of Chagas disease.
First phase of Chagas disease
If you get symptoms, they usually show up within the first few weeks and are mid during the first (or acute) phase. This first stage can last a few weeks to months.
During the first phase, you may get:
- Fever, fatigue, or other flu-like symptoms
- A rash
- A sore where the parasite has entered the body
- Vomiting, diarrhea, or loss of appetite
- Swollen eyelids, if the parasite has entered through the eyes (known as Romaña’s sign)
These early symptoms – if they happen at all – usually fade on their own after two to four months. But you're at a higher risk of complications if you have a weakened immune system.
Second phase of Chagas disease
While the symptoms may go away, the parasite remains in your body. It can stay dormant for years or even decades. If the disease enters its second (or chronic) phase, it can cause serious heart and intestinal problems.
If you have chronic Chagas disease, you may have:
- An enlarged heart, esophagus, or colon
- Heart failure
- An altered heart rhythm
- Blood clots
- Sudden cardiac arrest
When to call the doctor
Call your doctor to get tested if you've:
- Been to an area where there's Chagas disease
- Had symptoms of Chagas disease
How Do You Treat Chagas Disease?
Chagas disease is easiest to treat during the first phase with medications that can kill the parasite. But the lack of symptoms can make it tough to spot early on.
If you think you have it, your doctor can give you blood tests. If they show you're infected, you'll need an electrocardiogram (EKG) and other heart tests to check for any heart problems.
Two drugs can treat the disease and kill the parasite:
- Benznidazole
- Nifurtimox (Lampit)
They work well if taken soon after infection. The longer someone's had Chagas disease, the less likely the drugs are to work. Pregnant women can't take them, but infected newborns can.
The medications must be taken for up to two months and can cause serious side effects, especially in older people. So if you're an adult in the U.S., your doctor may use these medicines "off-label." That's because the medicines are only approved for use in children.
Benznidazole is approved for children 2-13 years old, and nifurtimox is for children up to 17 years old.
Can Chagas Disease Be Prevented?
There is no vaccine. The best way to prevent it is by avoiding triatomine bugs. They tend to live in homes made from mud, adobe, straw, and palm thatch, according to the CDC.
If you're traveling in Latin America, it's best to stay out of these types of dwellings. You can also protect yourself by using nets to cover your bed while sleeping.
Since 2007, blood banks in the U.S. have begun screening for Chagas, so there's no longer any chance of infection from the blood supply in the U.S.
Takeaways
Chagas disease, also known as "kissing bug disease," is caused by a parasite called Trypanosoma cruzi. Most people don't get symptoms during the first phase, but you can feel like you have the flu. Only a third of people with a Chagas infection develop problems long-term – usually heart and digestive disease. If you've been in an area where there's Chagas disease and have symptoms, call your doctor to get treated right away.
Chagas Disease FAQs
What does a kissing bug bite feel like?
Chagas bugs have tiny, very thin mouthparts. So you won't feel anything if they bite you. And because they're more active at night, you'll likely be asleep.
How does the Chagas bug spread the disease?
The kissing bug carries the parasite in its poop. So you don't get infected directly from the kissing bug's bite. You get infected by scratching the kissing bug poop into your bite. And you can get the poop on your hand and get infected if you touch your eye or mouth afterward.
Can my dog get bitten by a kissing bug?
Yes, but your dog is more likely to eat a kissing bug. If your dog gets bitten or eats an infected Chagas bug, they can get the parasite. Talk to your vet, but best way to protect your pet is to keep your pet away from Chagas bugs.