Potential geographic displacement of Chagas disease vectors under climate change

Abstract

Climate change is projected to profoundly alter global biodiversity with significant implications for vector-borne disease dynamics. In tropical regions, rising temperatures and shifting precipitation patterns influence the distribution and behaviour of insect disease vectors, thereby affecting disease transmission cycles. Chagas disease, caused by the Trypanosoma cruzi and transmitted by triatomine bugs, is a major public health concern in Latin America. Brazil is particularly vulnerable to climate-driven vector redistribution due to its vast land area, diverse ecosystems and rapid land-use changes. Using ecological niche modelling and 11,640 unique occurrence records, we assessed the potential geographic displacement of 55 triatomine species under two climate scenarios: a moderate warming scenario (SSP2-4.5) and a high-emissions scenario (SSP5-8.5) for 2050 and 2080. While projections for 2050 suggest stability in vector distributions, our models indicate a substantial shift by 2080, with increasing suitability for vector populations in the Brazilian Amazon, particularly in the deforestation arc. This expansion could exacerbate Chagas disease risk in previously unaffected regions, where socioeconomically vulnerable populations face poor housing conditions that facilitate vector-human contact. Our findings underscore the urgent need for proactive vector surveillance, public health interventions and climate-adaptive disease prevention strategies to mitigate potential epidemiological risks associated with climate change.