Their insect name is triatomines, but people call them “kissing bugs” for a rather unpleasant reason — they tend to bite people on the face.

Kissing bugs carry a parasite called Trypanosoma cruzi. They pick up this parasite by feeding on an infected person or animal. The parasite then lives in the kissing bug’s intestines and feces.

If feces containing this parasite get inside your body, you become infected. The infection is called Chagas disease.

Kissing bugs are nocturnal. This means they come out at night to feed. Usually the person is sleeping, and the bite doesn’t hurt. You may not even know you’ve been bitten.

Kissing bugs bite by injecting saliva that has an anesthetic property into the skin. It typically takes between 20 and 30 minutes for a bug to feed. The bug may bite anywhere from 2 to 15 times. Typically, the bug will bite a person on their face.

Most people don’t have a skin reaction when a kissing bug bites them. The bite looks like any other bug bite except there’s usually a cluster of bites together in one spot.

People who are sensitive to the bug’s saliva, may experience a reaction to the bite. This is usually only mild itching, redness, and swelling, but occasionally, a kissing bug bite causes a severe allergic reaction.

If you’ve been infected with the Trypanosoma cruzi parasite, a small area of redness and swelling that feels hard, called a chagoma, may form at the bite site a week or two after being bitten. If the bug’s feces are accidentally rubbed into the eye or the bite is near one, a distinctive swelling around that eye, known as Romaña’s sign, can occur.

Severe allergic reaction

Some people experience anaphylaxis after being bitten. This is a life-threatening allergic reaction that comes on suddenly. It can make it hard to breathe and lower blood pressure to dangerous levels. It requires immediate treatment.

Chagas disease

Chagas disease is endemic to Mexico, Central America, and South America. According to the Centers for Disease Control and Prevention (CDC), up to eight million people in these areas have the infection.

The CDC estimates over 300,000 people in the United States have the parasite. There are kissing bugs in the southern states but only rarely do these bugs transmit the parasite. Most people with Chagas disease in the United States were infected in the endemic areas.

Chagas disease is a severe complication of a kissing bug’s bite. It’s caused by being infected with a parasite called Trypanosoma cruzi that lives in a kissing bug’s intestines and feces. Not all people bitten by kissing bugs get Chagas disease. This is because you only get the disease if infected feces from the parasite get into your body.

After the kissing bug bites and feeds on a person’s blood, kissing bugs defecate. An infection can occur if the feces enter the body through the mouth nose or eyes or any opening in the skin. This can happen if you scratch or touch the bite and accidentally transfer the feces. Feces can also get in through the bite. Scratching or rubbing the bite increases the chances of this happening.

The first few weeks of the infection are what’s known as the acute phase. Most people have no symptoms or only very mild flu-like symptoms. These can include fever, body aches, a rash, and swollen glands. The symptoms are a reaction to the high number of parasites circulating in the blood.

The symptoms improve without treatment as the number of parasites in the bloodstream decreases. This is the chronic phase. The parasite is still in the body, but most people don’t have any more symptoms.

However, according to the Centers for Disease Control and Prevention (CDC), an estimated 20 to 30 percent of people with Chagas disease experience symptoms 10 to 25 years later. The symptoms are severe and can be life-threatening. They can include:

If treated early, the chronic phase can be avoided. It’s important to seek treatment early if you think a kissing bug has bitten you because there’s no cure for Chagas disease once it becomes chronic.

If your doctor diagnoses you with Chagas disease, they can prescribe antiparasitic medications like benznidazole and nifurtimox. Neither are readily available.

  • Benznidazole. This medication is FDA-approved for children 2 to 12. It’s not available in U.S. pharmacies, but can be obtained by doctors from the manufacturer’s website.
  • Nifurtimox. This isn’t FDA approved. It can be obtained from the CDC as an investigational drug.

Chagas disease needs to be treated early. Once the disease reaches the chronic phase, medications won’t cure it.

Antiparasitic medication is given to anyone in the acute phase to kill the parasites and stop the disease from becoming chronic. It’s also sometimes given to people in the chronic phase.

Medications can’t cure the disease after it becomes chronic, but it may slow the progression of the disease and help avoid the life-threatening complications. People with chronic disease who should be treated are:

  • anyone under 18
  • anyone under 50 who doesn’t have advanced cardiomyopathy

You should see a doctor if you:

  • live in the southern half of the United States, Central America, Mexico, or South America and have clustered insect bites on your body, especially your face
  • have seen kissing bugs in your home (see photos below)
  • are experiencing symptoms that could be due to Chagas disease

During the day, kissing bugs usually live in mud, straw, and adobe. These materials are often used to build homes in the endemic areas of Mexico, South America, and Latin America. If you visit these areas, try to avoid sleeping in structures made of these materials. If you do sleep in them, take the following precautions:

  • surround your bed with insecticide-coated netting
  • spray insecticides to kill the bugs in the area
  • apply bug spray regularly

If you live in the Southern United States and see kissing bugs:

  • seal cracks and crevices in your home with silicone-based caulk
  • repair any holes or damages in window screens
  • remove debris or leaves within 20 feet of the home
  • have pets sleep indoors to keep the bugs from biting them at night and transmitting the virus to people
  • clean all surfaces with a bleach or insecticidal solution

A professional exterminator can kill the kissing bugs if you’ve seen them in your home. If you think you see a kissing bug, try to capture it while wearing gloves or with a container. Do not touch the bug directly and clean all surfaces with a bleach solution if you’ve seen kissing bugs in your home.

Kissing bugs can resemble many other bugs naturally present in the United States, such as the Western corsair, leaf-footed bug, and wheel bug. Key aspects of a kissing bug’s appearance include:

  • cone-shaped head
  • long, oval-shaped body with antennae
  • about 0.5 to 1 inch in length
  • light brown to black body (some bugs have yellow, red, or tan markings on their bodies)
  • six legs

Kissing bugs don’t always cause Chagas disease, but if you think you’ve been bitten, see your doctor right away. Early treatment is critical to prevent Chagas disease from reaching the chronic stage.

Keeping your home bug-free and notifying your doctor if you have bites or symptoms of Chagas disease can help you stay as healthy as possible.