The Association Between Ambient Temperature and Snakebite in Georgia, USA: A Case‐Crossover Study

Abstract

Abstract The World Health Organization has identified snakebite envenoming as a highest priority neglected tropical disease, yet there is a dearth of epidemiologic research on environmental risk factors, including outdoor temperature. Temperature may affect snakebites through human behavior or snake behavior; snakes are ectotherms, meaning outdoor temperatures influence their internal body temperature and thus their behavior. Here we investigate the relationship between short‐term temperature and snakebites in Georgia, one of the most biodiverse US states in terms of herpetofauna. We acquired emergency department (ED) visit data for Georgia between 1 January 2014 and 31 December 2020. Visits for venomous and non‐venomous snakebites were identified using diagnosis codes. For comparison, we also considered visits for non‐snake (e.g., insects, spiders, scorpions) envenomation. Daily meteorology from the Daymet 1 km product was linked to patient residential ZIP codes. We applied a case‐crossover design to estimate associations of daily maximum temperature and snakebite ED visits. During the 7‐year study period, there were 3,908 visits for venomous snakebites, 1,124 visits for non‐venomous bites and 65,187 visits for non‐snake envenomation. Across the entire period, a 1°C increase in same‐day maximum temperature was associated with a 5.6% (95%CI: 4.0–7.3) increase in the odds of venomous snakebite and a 5.8% (95%CI: 3.0–8.8) increase in non‐venomous snakebite. Associations were strongest in the spring. We also observed a positive and significant (p < 0.05) association for non‐snake envenomation, albeit slightly smaller and more consistent across seasons compared to those for snakebites.

Keywords

• temperature
• snakebite
• climate change
• epidemiology
• ecology