‘Kissing bug’ disease is now endemic in the U.S., CDC says. What is it?

“Kissing bug” disease, also known as Chagas disease, is now considered an endemic illness in the United States, the Centers for Disease Control and Prevention said earlier this month. Scientists have long warned that the potentially deadly disease is spreading, especially across southern states.

A disease is usually considered endemic when it is constantly present within a specific area or population. Worldwide, more than 100 million people are considered at risk of being infected with Chagas disease, according to the World Health Organization.

Here’s what to know.

What’s ‘kissing bug’ disease?

Chagas disease is caused by the parasite Trypanosoma cruzi, which is found in the feces of the triatomine bug — commonly known as the “kissing bug” because it often bites people’s faces. The insects become infected when they feed on the blood of hosts carrying the parasite.

The disease can spread to humans and animals in several ways, such as when contaminated feces are accidentally rubbed into open wounds, the eyes or the mouth.

The disease can also be transmitted congenitally, from mother to child, or through contaminated blood transfusions, though these types of transmission are rarer.

Several animals, including dogs, can host the parasite, and there has been growing evidence of local canine infections in states such as Texas and California.

What are the signs and symptoms?

Chagas disease has two phases: acute and chronic. The acute phase, which occurs in the first few weeks or months after infection, can be asymptomatic. It can also cause mild symptoms such as fever, fatigue, body aches or swelling of the eyelid. Seeking treatment at this stage is very important, according to the CDC.

In the absence of treatment, chronic Chagas disease can develop and last for several years or even a lifetime. As many as 30% of those with Chagas disease can develop serious health complications that can lead to conditions such as heart failure or an enlarged esophagus or colon, the CDC says. Others may remain asymptomatic.

The disease is “often fatal by the time symptoms develop,” said Paula Stigler Granados, an associate professor at the San Diego State University School of Public Health.

Doctors are able to test humans and pets for the disease using a variety of methods.

Where in the U.S. is Chagas disease spreading?

Non-imported cases of Chagas disease have been identified in at least eight U.S. states so far: California, Arizona, Texas, Tennessee, Louisiana, Missouri, Mississippi and Arkansas.

Peter Hotez, dean of the National School of Tropical Medicine at the Baylor College of Medicine, said that there has long been a misconception about where the disease can spread.

“We always think of this as a problem purely affecting low and middle-income countries,” he said. “But in fact, there’s quite a high percentage of these illnesses in wealthy countries like the U.S.”

The bloodsucking insects “occur naturally in the southern half of the country and have been identified in 32 states,” according to the CDC. Kissing bugs are otherwise often found in rural parts of Mexico, Central America and South America.

How is Chagas disease treated?

There are currently no vaccines or drugs to prevent Chagas disease, according to the CDC. In the U.S., two antiparasitic medicines have been approved by the U.S. Food and Drug Administration for those who are suspected to have been infected.

When traveling to countries where the disease is present, the CDC recommends reducing the risk of contact with infected kissing bugs, which are sometimes found in the cracks and crevices of poorly constructed houses and can survive both indoors and outdoors.

“We don’t have sufficient levels of active surveillance to look for these diseases,” Hotez said. “If you don’t look, you don’t find — and that’s been a big problem.”

While recognizing the disease as endemic is a “great first step,” Granados said, “labeling it as endemic will not change the fact that we don’t have systematic surveillance or the resources to support it.”

The CDC also recommends spraying areas with long-lasting insecticides, wearing clothing that covers the skin and avoiding raw vegetables and unpeeled fruits in areas where Chagas disease has been detected. Pet owners can help prevent Chagas disease from reaching their furry friends by using anti-flea and tick medications such as Nexgard and Bravecto.