© S. Priyadarshini

Researchers from the Indian Institute of Science in Bangalore, have found that commercially available anivenoms are ineffective in alleviating the toxic effects of snake bites1. Apart from pointing out the inefficiency of current antivenom therapies, the research highlights the need for an effective next-generation snakebite therapy in India.

Snakebites claim 46,000 lives and disable 140,000 people every year in India. Antivenoms are widely used to treat bites from the “big four” ‒ the spectacled cobra ( Naja naja ), the common krait ( Bungarus caeruleus ), Russell’s viper ( Daboia russelii ) and the saw-scaled viper ( Echis carinatus ) ‒ and other venomous snakes. However, these antivenoms are not designed to treat bites by a specific snake.

To assess the efficiency of existing antivenoms, the researchers, teaming up with scientists from the Madras Crocodile Bank Trust in Tamil Nadu and the Jerry Martin Project in Hunsur, India, analysed the protein compositions and toxicity profiles of the venoms of the “big four” and other snakes, and the venom-neutralising efficiency of the commercial antivenoms in India.

The researchers, led by Kartik Sunagar, found that the venoms of these snakes contain a wide range of toxins, with profound compositional diversity among different species and even within a single species. The commercial antivenoms were found to be poor at neutralising the toxic effects of various snake venoms.

Two specific antivenoms recognised the venom for the N . naja from Maharashtra more effectively than the venoms of the N . kaouthia from eastern- and north-eastern India.

The antivenoms were particularly poor against the East Indian snake venoms. One of the antivenoms completely failed to neutralise N . kaouthia venom from north-east India, despite it being the least toxic among the cobra venoms tested.

References

1. Laxme, R. R. S. et al. Beyond the ‘big four’: Venom profiling of the medically important yet neglected Indian snakes reveals disturbing antivenom deficiencies. PLOS. Negl. Trop. Dis. (2019) doi: 10.1371/journal.pntd.0007899