Climate Change May Trigger New Snakebite Hotspots In India, Heightening Public Health Risks: Study

India, which records the highest number of snakebite fatalities worldwide, faces a looming public health crisis as climate change threatens to expand the habitats of venomous snakes into new regions, including northern and northeastern states, warns a new study.

Such shifts will likely increase human-snake encounters, posing fresh challenges for healthcare delivery and snakebite management in India which is already witnessing climate change-induced extreme weather events such as rains, drought and floods.

The research, conducted by the Dibru-Saikhowa Conservation Society, Tinsukia, in collaboration with other institutions, highlights the potential geographic redistribution of the “Big Four” venomous snakes—Bungarus caeruleus (common krait), Daboia russelii (Russell’s viper), Echis carinatus (saw-scaled viper), and Naja naja (Indian cobra).

These species are responsible for the majority of envenomation cases in India, yet their evolving distribution patterns due to climate shifts have not been comprehensively assessed until now.

The study titled ‘Future of Snakebite Risk in India: Consequence of Climate Change and the Shifting Habitats of the Big Four Species in Next Five Decades’, published in PLOS Neglected Tropical Diseases, integrates climate-driven species distribution models with socioeconomic and healthcare data.

“The resulting snakebite risk index predicts an expansion of snakebite-prone areas, particularly in the northern and northeastern parts of the country over the next 50 years,” says the study.

The authors emphasise that climate change is not merely an environmental concern but a pressing public health issue.

“Altered geographic ranges of venomous snakes will likely increase human-snake interactions, complicating medical management,” the study notes. Consequently, there is an urgent need to strengthen healthcare delivery systems, improve antivenom research and production, and raise community awareness to mitigate the emerging risks.

Recognised by WHO as a neglected tropical disease since 2017, snakebite envenoming causes an estimated 81,000 to 138,000 deaths globally every year, with India accounting for nearly half of this burden.

According to government data, India reports an estimated 46,000 to 60,000 annual deaths from snakebites, disproportionately affecting rural, tribal, and economically vulnerable populations. These communities often face inadequate healthcare infrastructure, limited access to effective antivenoms, and delayed treatment, factors that exacerbate morbidity and mortality.

Despite India’s initiatives such as the National Action Plan for Prevention and Control of Snakebite Envenoming (NAP-SE), experts caution that the healthcare system remains ill-prepared for the increasing burden. The recent global report ‘Time to Bite Back’ by the Global Snakebite Taskforce speaks volumes about this gap, underscoring the necessity for comprehensive strategies to halve snakebite-related deaths and disabilities by 2030, in line with World Health Organization targets.

Dr. Yogesh Jain, public health physician and co-author of the report, highlighted compounding factors including treatment delays, dependence on traditional healers, inconsistent antivenom efficacy, and poor healthcare infrastructure, all of which hinder effective management of snakebite cases.

The report was unveiled at the 78th World Health Assembly in Geneva by the Global Snakebite Taskforce, the strategic arm of Strike Out Snakebite (SOS), a global campaign dedicated to reducing deaths and disabilities caused by snakebite envenoming.

Survivors frequently suffer long-term disabilities, amplifying the socioeconomic impact. However, according to health experts, majority of snakebite envenomation deaths can be avoided with prompt availability to safe and effective antivenoms, timely transport and referral.

The health experts say that administration of polyvalent anti-snake venom (ASV) containing antibodies against cobra, Russell’s viper, common krait and saw scaled viper is effective in 80% of the snakebite cases, however, lack of trained human resources and health facilities to treat snakebite patients remains a cause of concern. “Also, the unavailability of data on incidence, morbidity, mortality, socio-economic burden, treatment patterns etc. are the major hindrances in planning for mitigation of snakebite in India.”

In a significant step, the Union Health Ministry last year declared snakebite cases and fatalities as a “notifiable disease”, aiming to improve surveillance and response.

In March, 2024, Apurva Chandra, the then Union Health Secretary had launched the NAP-SE, with a vision to reduce snakebite deaths by halve by 2030.

It provides a broad framework for states to develop their own action plan for management, prevention and control of snakebites through the ‘One Health’ approach.