Abstract
BACKGROUND: Oral transmission of Chagas disease has been registered in rural and periurban areas of South America. In Brazil, outbreaks have involved food, sugar cane juice, water, or soup contaminated with infected triatomines or their feces. Here, we report an investigation into an acute Chagas disease outbreak in a rural area of the municipality of Serrolândia, in the semi-arid region of Bahia, Brazil. METHODS: We conducted a descriptive study based on primary care information, epidemiological evaluation, entomological surveillance, and molecular analysis. The investigation began after the death of a 12-year-old child. The study population included triatomines, animals (one opossum, three cats, and two dogs), and a human family of five individuals. We performed serological diagnosis of family members, Trypanosoma cruzi molecular detection and genotyping in collected samples, and triatomine blood meal analysis. RESULTS: Among the five family members, four tested positive for acute Chagas disease. All affected individuals reported ingesting acerola juice from fruits grown on their property, except for case 5, who did not consume the juice or fresh fruit and tested negative for T. cruzi. During the investigation, we captured 21 triatomines and collected blood samples from sylvatic and domestic animals. TcI haplotypes show a close relationship between the parasites found in vectors and those detected in a single human case and in the wild reservoir captured, respectively, reinforcing the vector/oral transmission hypothesis and the maintenance of the T. cruzi anthropozoonotic cycle in the region. CONCLUSIONS: This study describes the investigation of an acute Chagas disease outbreak in the Serrolândia municipality, and based on that, we conclude that the infection occurred through the vector/oral route via ingestion of T. cruzi-contaminated fresh acerola fruit or juice. Our findings underscore the need for improved surveillance and preventive measures in areas vulnerable to Chagas disease.