ECOLOGICAL STUDY OF ACCIDENTS CAUSED BY CROTALUS SP SNAKES IN BRAZIL BETWEEN 2010 AND 2023

Abstract

INTRODUCTION: Accidents caused by venomous snakes represent a major public health challenge, especially in rural regions of tropical-climate countries. It is estimated that approximately 5 million snakebite envenomations occur worldwide each year, resulting in around 100,000 deaths. In Brazil, the genera Bothrops and Crotalus stand out, with the latter being associated with higher lethality and severe clinical manifestations such as neurotoxicity, myotoxicity, and acute renal failure. In addition to clinical repercussions, these accidents lead to significant economic and social impacts, particularly because they affect individuals of productive age living in rural areas. Early administration of antivenom is essential to reduce mortality and complications resulting from envenomation. OBJECTIVE: To investigate the epidemiological profile of accidents caused by snakes of the Crotalus genus in Brazil between 2010 and 2023, analyzing mortality, regional distribution, seasonal variation, sex, age group, and anatomical site of the bite, in order to identify relevant patterns for surveillance and public health. METHODOLOGY: This is an ecological, descriptive, and retrospective study based on secondary data extracted from the Notifiable Diseases Information System (SINAN/DATASUS). All cases recorded in the country between 2010 and 2023 were included. The variables analyzed comprised: absolute number of cases and deaths, mortality rate, regional distribution, seasonality, sex, age group, and bite location. Statistical analysis was performed using descriptive statistics, with absolute and relative frequencies, processed in Microsoft Excel. RESULTS AND DISCUSSION: A continuous increase in the number of reported snakebite accidents was observed, rising from 124,920 cases in 2010 to 340,819 in 2023. In total, 296,475 Bothrops accidents and 34,080 Crotalus accidents were recorded, with mortality rates of 0.42% and 0.95%, respectively. Crotalus cases were more concentrated in the Northeast (37.8%) and Southeast (35.2%) regions, and were more frequent during the warm and rainy months (January to March), which accounted for 34% of notifications. Most affected individuals were male (80%) and adults of productive age (20–59 years: 22,209 cases), reflecting higher occupational exposure in agricultural activities. Bites occurred mainly on the lower limbs (65.2%), followed by upper limbs (20.2%), often during inadvertent handling of snakes in rural work environments. These epidemiological variations appear to be associated with environmental, climatic, and occupational factors that increase the risk of contact with snakes. CONCLUSIONS: Crotalus snake accidents predominantly affected adult men living in rural areas, especially during rainy months, with injuries most frequently occurring on the lower limbs. These findings reinforce the importance of public policies aimed at prevention, such as the provision of personal protective equipment (PPE) and the training of health teams for timely diagnosis and treatment. Among the limitations of the study, the use of secondary data stands out, as they are subject to underreporting and lack detailed clinical information. Nevertheless, the results contribute to guiding future research on environmental determinants and the effectiveness of antivenom therapy in different regions of the country.