San Diego County health officials have confirmed the area’s first locally acquired case of Chagas disease, a parasitic infection sometimes called the “kissing bug” disease.
According to county public health officials, the case was discovered through routine blood donation screening of a donor who had no symptoms. While Chagas disease is typically associated with rural areas of Latin America, researchers say evidence suggests the infection is also present in parts of the United States.
“The identification of a locally acquired Chagas case reminds us that this disease is not limited to Latin America,” Dr. Sayon Thihalilopawan, the county’s public health officer, said in a statement. “Our priority is to ensure that residents and healthcare providers have the information they need to stay safe.”
San Diego County officials made Chagas disease locally reportable in 2024, meaning healthcare providers and laboratories will have to notify the county if cases are identified. The change was intended to improve tracking and awareness of the disease. Since then, the county has received 22 reports and four cases have been confirmed. The case announced on Monday, July 6 is the first case the county has identified as locally acquired, meaning the infection occurred in San Diego County rather than through travel or exposure elsewhere.
Here’s what to know about Chagas disease, including how it’s spread, symptoms to look for and why researchers say the infection may be more common in the United States than previously thought.
What is Chagas disease?
Chagas disease is caused by the parasite Trypanosoma cruzi, which can be transmitted by triatomine insects, commonly known as kissing bugs.
Insects can become vectors after eating an infected animal or person. They spread the parasite through their feces, which can enter the body through cuts in the skin or through contact with the eyes or mouth.
In Latin America, kissing bugs often live in the cracks of houses made of materials such as mud and straw. In San Diego County, officials said the locally found species typically inhabits rodent nests, making outdoor activities such as camping a potential exposure risk.
What are the symptoms of Chagas or ‘kissing bug disease’?
Many people infected with Chagas disease experience no symptoms or only mild illness during the early stages. Symptoms may include fever, headache, cough, stomach pain, fatigue, diarrhea, loss of appetite, or swelling near the bite site.
Some infections may go unnoticed for years. About 30% to 40% of infected people may eventually develop serious complications affecting the heart or digestive system decades later, including an enlarged heart, irregular heart rhythm, heart failure or digestive system problems, NBC San Diego reports.
If the infection is not treated, the disease can spread from the pregnant person to the baby.
Researchers say disease may be underdiagnosed in US
A group of researchers recently argued that Chagas disease should be considered endemic in the United States, meaning that it occurs regularly in certain areas.
Researchers from the University of Florida, Texas A&M University, the University of California and the Texas Department of State Health Services investigated reports of the kissing bug across the country. Since 2013, Texas A&M University’s Kissing Bug Community Science Program has received approximately 10,000 kissing bug reports from 31 states.
According to Sarah Hammer, a Texas A&M professor involved in the research, the test found that the parasite was present in about half of the subgroup of insects that causes Chagas disease. Cases of human infection have been reported in eight states in America.
There is no national reporting system tracking all cases of Chagas because the disease is not federally classified as a nationally notable condition.
How can people protect themselves?
Health officials advise travelers visiting areas where Chagas disease is common to wear protective clothing, use insect repellent, sleep indoors, use insecticide-treated bed nets and avoid unpeeled or uncooked fruits and vegetables.
People who live in parts of Latin America where Chagas is common may also want to consider screening, especially pregnant women, NBC San Diego reports.
Reporting by Anthony Thompson and Greta Cross, USA TODAY. USA TODAY Network via Reuters Connect.