The number of people poisoned or killed each year by snake bites could be far higher than the estimates used until now.
An international team has reassessed this global health issue, 17 years after a previous benchmark estimate. The researchers examined published studies on bites, envenomings and deaths through March 31, 2025. Envenoming means that the snake actually injected venom and caused effects in the body.
Ahaetulla prasina (Asian vine snake), Kaeng Krachan National Park, Thailand
CC BY-SA 2.0 · Wikimedia
Their low estimate reaches 2.1 million envenomings and 274,000 deaths per year. In the high-end scenario, the figures rise to as many as 7 million envenomings and 513,000 deaths. These numbers come from a statistical model, so they do not represent a direct count of every victim.
Why such uncertainty? Many bites occur in rural areas where medical data remain incomplete. Some victims do not go to a healthcare facility, particularly when care is far away or difficult to access. Hospital records then capture only part of the actual number of cases.
For their research, the researchers assembled several types of data. Their final selection included 84 publications considered sufficiently robust, along with six sources from ministries, poison control centers and health agencies, among others. The model also takes geographic, social, agricultural and environmental factors into account.
The resulting distribution is highly uneven. Sub-Saharan Africa would account for about 45% of global envenomings and deaths. South Asia and Southeast Asia are also among the regions most affected. Low-income countries have the highest rates.
These findings substantially change the order of magnitude compared with the global assessment published in 2008. That assessment estimated between 420,000 and 1.8 million annual envenomings, with 20,000 to 94,000 deaths. Since then, more local studies and population surveys have revealed cases that had escaped hospital statistics.
The authors remain cautious about their own figures. In several countries, direct observations remain rare and data-collection methods differ considerably. Estimates therefore rely more heavily on modeling in regions where information is lacking, widening their uncertainty range.
New surveys conducted directly among populations are now needed, particularly in Sub-Saharan Africa. More precise data would make it possible to better allocate antivenoms, medical equipment and trained personnel to areas where bites cause the most deaths.