A recent study led by members of our network , from Centre for Ecological Sciences , Indian Institute of Science, Bangalore, found that the venom of Russell’s vipers shows differences in composition and toxicity based on the geographical location. They also found that the commercial antivenom treatment for Russell’s viper venom works as marketed for most populations of this snake, except in North India. This in contrast to a study published a few months ago on spectacled cobra by the same authors, which showed similar variation in venom based on location, but the preclinical effectiveness of commercial antivenoms was not found to be not effective against most populations.
Kartik Sunagar the senior author of the study says , “We show that you cannot really predict the clinical or preclinical outcomes just by observing venom variation across populations. Instead, well-designed clinical and preclinical studies are the only way to accurately test the effectiveness of commercial antivenoms.”
In order to ensure that antivenoms are more effective against variants of snake venom, researchers highlight the need for production of region-specific antivenoms. Senji Laxme, Suyog Khochare and Saurabh Attarde, who are the joint first authors in these studies said that, “Research outcomes of the spectacled cobra and Russell’s viper studies, and our previous work on the ‘neglected many’ suggest that the commercial antivenom fails to neutralise the venoms of three of the big four snakes in the north Indian regions. Coincidentally, these regions are among the major snakebite hotspots in the country. To ensure effective snakebite mitigation, the development of regional antivenoms with venoms sourced from the medically important snakes of the respective regions is the need of the hour “.
RR Senji Laxme, Saurabh Attarde, Suyog Khochare et al. Biogeographical venom variation in the Indian spectacled cobra (Naja naja) underscores the pressing need for pan-India efficacious snakebite therapy, PLoS Neglected Tropical Diseases (2021).
RR Senji Laxme, Suyog Khochare, Saurabh Attarde, et al. Biogeographic venom variation in Russell’s viper (Daboia russelii) and the preclinical inefficacy of antivenom therapy in snakebite hotspots, PLoS Neglected Tropical Diseases (2021).
Sections of the note are from the IISc press release which can be read here.