San Diego County Confirms First Locally Acquired Chagas Case

County health officials have confirmed the region's first locally acquired case of Chagas disease after it was detected during routine screening of a blood donor who showed no symptoms. The disease, traditionally associated with rural Latin America where the kissing bug inhabits mud and straw homes, can also be transmitted by a local bug species that lives in rodent nests, making outdoor activities a potential risk factor.

"Identifying a locally acquired Chagas case reminds us that this disease is not limited to Latin America," said Dr. Sayone Thihalilopavan, County Public Health Officer. "Our priority is making sure residents, and healthcare providers have the information they need to stay protected."

Early infection often produces mild or no symptoms, resembling a flu with fever, headache, cough, abdominal pain or swelling at the bite site. Untreated cases may lead to serious heart and gastrointestinal complications in 30 to 40 percent of patients years later, and the disease can be passed to infants during pregnancy.

The county made Chagas disease a reportable condition in 2024, receiving 22 reports and confirming four cases to date; this is the first confirmed locally transmitted infection. Public health staff are working with medical providers to investigate cases, monitor transmission and offer clinical guidance.

Officials advise travelers to endemic regions to wear protective clothing, use insect repellent and insecticide-treated bed nets, sleep indoors and avoid unpeeled or uncooked produce. Residents who have lived in Latin America, especially pregnant women, are encouraged to consider screening.