What is Chagas disease, the deadly condition caused by the kissing bug?

Here is what to know about the disease.

What is it?

According to the Centers for Disease Control and Prevention, Chagas disease is named after the Brazilian physician who discovered it in 1909. It is caused by Trypanosoma cruzi, a parasite that transmits the disease to animals and people through insects. It is only found in the Americas, particularly rural areas of Latin America where there is widespread poverty. Still, triatomine bugs have been reported in more than half of U.S. states, including Hawaii and the south and southwest regions of the country.

How does it spread?

Chagas disease does not spread from person-to-person in the way a cold or flu does. Instead, it spreads though vectorborne transmission, or transmission through animal hosts or vectors. In the case of Chagas disease, those vectors are blood sucking bugs called triatomine bugs. The bugs pass the parasites in their feces after biting an animal or person.

Related: Dangerous ‘kissing bug’ spreading north from South America, CDC warns

Triatomine bugs are called "kissing bugs" because they tend to bite people on the face, emerging at night. They hide in walls and roofs during the day, according to the CDC. People can also get infected from a pregnant person to their baby, eating uncooked food contaminated with feces from infected bugs, and through blood transfusions, organ transplants and accidental exposure in a laboratory.

The large-scale movements of populations from rural to urban areas of Latin America and other regions has contributed to its spread geographically, according to the CDC. The organization estimates that as many as 8 million people living in Mexico, Central America and South America have Chagas disease.

According to research from Texas A&M University, dogs are also at risk of infection, particularly in kennels. Other animals found to be infected with the parasite are mice, raccoons, foxes, possums, armadillos, coyotes and skunks.

What are the symptoms?

Infection is lifelong if the disease is not treated. It has an acute and chronic phase.

Symptoms in the acute phase, which can last a few weeks or months, include fever or swelling around the site where the parasite entered into the skin. After that phase, most of those infected go into a prolonged asymptomatic form of disease, called chronic indeterminate, in which they have few or no symptoms.

Credit: Michael Robinson Chavez

Credit: Michael Robinson Chavez

Most people never develop symptoms, but 20 to 30% of infected people develop life-threatening medical problems over the course of their lives, the CDC said. Complications from untreated infection include a dilated esophagus or colon, leading to difficulties with eating or passing stool, a dilated heart that pumps blood poorly and abnormal heart rhythms that can lead to sudden death.

Dogs can also be asymptomatic, but an infection can cause heart disease, abnormal heart rhythm and sudden death.

How is it treated?

According to the World Health Organization, Chagas disease can be treated with benznidazole and nifurtimox, antiparasitic treatments which are nearly 100 percent effective in curing the disease if given early in the acute phase. The longer a person has been infected, the less effective either medicine is in treating the disease.

Sympomtatic treatment can be used for people with gastrointestinal or cardiac problems, such as pacemakers and irregular heartbeat medication for those with chronic heart disease.

How can it be prevented?

There are no drugs or vaccines for preventing Chagas disease, but people living in high-quality, well-constructed facilities with screened hotel windows and doors or air conditioning have a low risk of exposure.

People living in or visiting infected areas should spray them with long-lasting insecticide and wear protective clothing, wearing insect repellent on exposed skin. Salads, uncooked food, unpeeled fruit and unpasteurized fruit juices should be avoided in infested areas.

For public health, blood and organ donations are screened for the disease and early treatment of new cases help decrease its spread. WHO recommends newborns and children of infected mothers who have not had antiparasitic treatment should be screened for early diagnosis, treatment and prevention.