# Deforestation effects and house invasion by chagas disease vectors in Brazil

## TL;DR

Deforestation in Brazil is linked to increased presence of Chagas disease vectors in urban areas, raising transmission risks.

## Contribution

This study identifies deforestation and forest patches as key drivers of triatomine infestation in urban neighborhoods.

## Key findings

- Urban expansion replaced forest areas, increasing triatomine presence indoors.
- 50% of collected triatomines tested positive for Trypanosoma cruzi.
- Deforestation and forest patches within neighborhoods influence triatomine frequency.

## Abstract

We analyzed how deforestation affects triatomine presence and distribution in Salvador, Bahia, Brazil, from 2007 to 2019. Using land change data from MapBiomas (1985–2022), we assessed land cover shifts, including forest, deforestation, and urbanization, and their impact on Trypanosoma cruzi vectors. Urban growth has largely replaced mixed-use and forest areas, bringing some populations closer to remnants of the forest and increasing triatomine presence indoors. We documented 1,518 triatomine records, with ~ 50% testing positive for T. cruzi. Statistical models showed that deforestation and the remaining forest patches within neighborhoods are key factors influencing triatomine frequency. This urban expansion raises the risk of parasite transmission among vulnerable groups. To mitigate this, we recommend enhanced surveillance, control strategies, and health education in high-risk neighborhoods, aiming to reduce exposure and prevent disease transmission associated with deforestation and habitat changes.

The online version contains supplementary material available at 10.1038/s41598-025-22086-z.