India is among the countries most dramatically affected by snakebite and accounts for almost half the total number of annual deaths in the world. Authors of the article entitled ‘Trends in snakebite mortality in India from 2000 to 2019 in a nationally representative mortality study’ analysed 2,833 snakebite deaths from 611,483 verbal autopsies from an earlier study1 and conducted a systematic literature review from 2000-2019 covering 87,590 snake bites.
The authors estimated that India had 1.2 million snakebite deaths (representing an average of 58,000 per year) from 2000 to 2019 with nearly half of the victims aged 30-69 and over a quarter being children under 15.
People living in densely populated low altitude agricultural areas in the states of Bihar, Jharkhand, Madhya Pradesh, Odisha, Uttar Pradesh, Andhra Pradesh (which includes Telangana, a recently defined state), Rajasthan and Gujarat, suffered 70% of deaths during the period 2001-2014, particularly during the rainy season when encounters between snakes and humans are more frequent at home and outdoors.
Russell’s viper (Daboia russelii) (Figure 1), kraits (Bungarus species) and cobras (Naja species; Figure 2) are among the most important biting snake species in India, yet other often unidentified species also represent a threat.
Left: Russel’s Viper (Photo:David Williams): Right: Speckled Cobra in a field near an agricultural worker.
(Photo: Ben Owens)
The World Health Organization (WHO) has set the target of reducing by half the number of deaths due to snakebite envenoming by 2030 and India’s efforts to prevent and control this disease will largely influence this global target.
“Since deaths are restricted mainly to lower altitude, intensely agricultural areas, during a single season of each year, this should make the annual epidemics easier to manage. India’s tremendous snakebite burden is staring us in the face and we need to act now” said Romulus Whitaker of the Centre for Herpetology/Madras Crocodile Bank. “Targeting these areas with education about simple methods, such as ‘snake-safe’ harvest practices, wearing rubber boots and gloves and using rechargeable torches (or mobile phone flashlights) could reduce the risk of snakebites.”
Need for more nationwide epidemiological studies in snakebite endemic countries
Additional nationally representative studies together with increasing mapping resolution and multi-sourced data granularity, including both hospital-based mortality and morbidity data including those collected at the community level, are needed for more targeted and effective public health interventions in other snakebite endemic countries.
The authors also noted that the Government of India’s official declaration of snakebite deaths in public hospitals during the period 2003 to 2015 was only 15,500, one tenth of the 154,000 snakebite deaths detected during this same period by the MDS from public and private hospitals.
“Our study directly quantified and identified the populations most affected by fatal snakebites in India. We showed that the overall lifetime risk of being killed by snakebite is about 1 in 250, but in some areas, the lifetime risk reaches 1 in 100” said Prabhat Jha, Director of the Centre for Global Health Research at the University of Toronto, Canada. “Ongoing direct measurement of mortality at local levels is key to achieving WHO’s global roadmap.”
To repair this gross under-reporting, the authors recommend that the Government of India designate and enforce snakebite as a ‘Notifiable Disease’ within the Integrated Disease Surveillance Program. Accurate snakebite data are essential if the Government of India’s strategies to reduce snakebite deaths are to succeed.
1Snakebite Mortality in India: A Nationally Representative Mortality Survey published in PLoS in 2011 and based on the Indian Million Death Study estimated 46,000 annual deaths caused by snakebite in India.