# Acute Chagas disease in Amazonia, western Pará: perspectives from medical assistance to genetic elucidation

## TL;DR

This study explores acute Chagas disease outbreaks in the Amazon region, highlighting clinical patterns, genetic diversity, and gaps in patient follow-up.

## Contribution

The study provides new insights into the clinical and genetic characteristics of acute Chagas disease outbreaks in the Amazon region.

## Key findings

- Two outbreaks were identified with different discrete typing units (TcIV and TcI) in the same municipality.
- Possible vertical transmission and a fatality rate of 12.5% were observed in one outbreak.
- No 'serological cure' was confirmed in follow-up tests up to 21 months after treatment.

## Abstract

The experience of the USP Tropical Medicine Centre (NUMETROP) team in providing medical care during acute Chagas disease (ACD) outbreaks in Santarém, Pará, motivated this study.

To study the epidemiological, clinical-laboratory, and socio-cultural aspects of confirmed cases of ACD in outbreaks in Santarém from March 2016 to March 2018.

Observational case series study of ACD outbreaks in two communities: Marimarituba in 2016 and Cachoeira do Aruã in 2017. Diagnostic characterisation included classification into discrete typing units (DTUs).

Eight cases were diagnosed as ACD TcIV in Marimarituba and seven cases were identified as ACD TcI in Cachoeira do Aruã. Women of childbearing age were numerous in both groups, and one miscarriage and two possible vertical transmissions were observed. Fever and rash were the most common findings in Marimarituba, with a fatality rate of 12.5%. In both outbreaks, serological surveillance was performed three to 21 months after treatment, with no confirmation of a “serological cure”.

We observed possible vertical transmission, diverse DTUs in the same municipality, and a lack of knowledge about patient outcomes. We highlight that, despite the importance of ACD in the Amazon region, there is no institutional follow-up of patients from diagnosis to cure.