Snakebites in the Brazilian Amazon: Epidemiological Surveillance and Primary Health Care as Axes of the SUS Response Capacity to Environmental Changes (2020–2025)

Abstract

Snakebites represent a severe public health challenge in the Amazon, influenced by socio-environmental factors and inequalities in healthcare access. This study analyzed the epidemiological profile of these injuries in the Northern Region of Brazil between 2020 and 2025, from the perspective of surveillance and Primary Health Care (PHC). An ecological and descriptive study was conducted using SINAN data, covering demographic, clinical, and temporal variables (2025 data are preliminary). Results indicate spatial heterogeneity, with a higher concentration of cases in the states of Pará, Amazonas, and Tocantins. The genus Bothrops predominated, followed by Crotalus, Micrurus, and Lachesis. There was a predominance of male victims and an increase in notifications until 2023. It was identified that extreme climate changes, such as the historic droughts of 2023–2024, altered local ecological dynamics, intensifying synanthropy processes. Natural habitat degradation and water stress forced the displacement of snakes toward anthropic areas in search of refuge, increasing the risk of human exposure. Although PHC and the strengthening of the Cold Chain have optimized response times, logistical bottlenecks in remote areas persist, worsened by low river navigability during critical periods. In conclusion, snake envenomation in the Amazon is a structural health issue exacerbated by the climate crisis, demanding resilient surveillance strategies that integrate environmental conservation with the SUS response capacity to mitigate territorial inequalities and ensure timely assistance.