DOENÇA DE CHAGAS AGUDA POR TRANSMISSÃO ORAL: MAIS DE UM SÉCULO APÓS A DESCOBERTA DE CARLOS CHAGAS, O MANEJO CONTINUA DESAFIADOR

Abstract

Acute Chagas disease (ACD) by oral transmission mainly affects low-visibility and lowincome individuals in tropical and subtropical areas. Even more than 100 years after its discovery, management remains challenging. Its spread to non-endemic areas has made it a global health problem. The objective of this work is to demonstrate the difficulties encountered in treating a real-life situation, through the description of the outbreak and the epidemiological, clinical and laboratory characteristics. This thesis examines an outbreak of 39 cases of ACD due to oral transmission through ingestion of bacaba juice that occurred in Pedro do Rosário, Maranhão, Brazil. A clinical and epidemiological investigation, including entomological search, was conducted. The inclusion criteria: all cases exposed to bacaba juice with confirmed ACD. Confirmation criteria were positive Giemsa stain and/or IgG seroconversion and/or a two-fold increase in IgG titer (laboratory criteria); clinical findings and epidemiological exposure and at least one positive IgG test (clinical-epidemiological criteria). Conventional polymerase chain reaction (PCR) was performed on 33 samples. The means were: age 32 years, with no gender difference; incubation period 13.8 days; time between the onset of symptoms and treatment was 16.6 days. The most common symptoms were fever and lymphadenopathy (90%). Patients had laboratory criteria in 66.6% of cases, clinical-epidemiological criteria in 23% and 10.2% had negative parasitological and serological tests, however, they were treated due to high suspicion. Test positivity rates were 69.7% (23/33) for Giemsa stain, 91.4% for serology and 100% (33/33) for PCR (including cases with negative parasitology and serology). All patients were treated with benznidazole. There was no death. After 4.5 years, IgG levels were reassessed in 26 individuals. Serological negativity was achieved in 30.7% (8/26) of cases, and IgG titers decreased by 7.6% (2/26). We encountered several barriers, including population vulnerability, dependence on rudimentary diagnostic techniques, lack of standardized molecular biology methods, and limited therapeutic options. This report highlights the importance of rapid surveillance and early treatment to prevent fatalities. We recommend the inclusion of PCR in the ACD diagnostic routine and the standardization of outbreak investigation and monitoring.