Overview
- San Diego County confirmed Monday that a routine blood-donor screening identified the region’s first known locally acquired Chagas infection in an asymptomatic donor.
- The county made Chagas a reportable disease in 2024 and has since received 22 reports and confirmed four cases, with this fourth case the first traced to local transmission.
- Chagas is caused by the parasite Trypanosoma cruzi and is usually spread when feces from an infected triatomine or “kissing” bug enter a bite; in California these bugs often live in rodent nests, making outdoor activities a noted exposure risk.
- Early infection is often mild or has no symptoms, but about 30 to 40 percent of infected people can develop serious heart or gastrointestinal disease years later and antiparasitic drugs (for example benznidazole and nifurtimox) work best in the acute phase.
- Public health officials are alerting clinicians, urging screening for people with travel or outdoor exposure, and advising residents to avoid rodent nests, seal gaps around homes, and report suspected kissing bugs to county health authorities for identification.