In majority of snakebite cases, the snake responsible for the bite remains unidentified. The traditional snakebite diagnostics method relies upon clinical symptoms and blood coagulation assays that do not provide accurate diagnosis which is important for epidemiological as well as diagnostics point of view. On the other hand, high batch-to-batch variations in antibody performance limit its application for diagnostic assays. In recent years, nucleic acid aptamers have emerged as a strong chemical rival of antibodies due to several obvious advantages, including but not limited to in vitro generation, synthetic nature, ease of functionalization, high stability and adaptability to various diagnostic formats. In the current study, we have rationally truncated an aptamer developed for α-Toxin of Bungarus multicinctus and demonstrated its utility for the detection of venom of Bungarus caeruleus. The truncated aptamer α-Tox-T2 (26mer) is found to have greater affinity than its 40-mer parent counterpart α-Tox-FL. The truncated aptamers are characterized and compared with parent aptamer for their binding, selectivity, affinity, alteration in secondary structure and limit of detection. Altogether, our findings establish the cross-species application of a DNA aptamer generated for α-Toxin of Bungarus multicinctus (a snake found in Taiwan and China) for the reliable detection of venom of Bungarus caeruleus (a snake found in the Indian subcontinent).

Snakebite incidence at least partly depends on the biology of the snakes involved. However, studies of snake biology have been largely neglected in favour of anthropic factors, with the exception of taxonomy, which has been recognised for some decades to affect the design of antivenoms. Despite this, within-species venom variation and the unpredictability of the correlation with antivenom cross-reactivity has continued to be problematic. Meanwhile, other aspects of snake biology, including behaviour, spatial ecology and activity patterns, distribution, and population demography, which can contribute to snakebite mitigation and prevention, remain underfunded and understudied. Here, we review the literature relevant to these aspects of snakebite and illustrate how demographic, spatial, and behavioural studies can improve our understanding of why snakebites occur and provide evidence for prevention strategies. We identify the large gaps that remain to be filled and urge that, in the future, data and relevant metadata be shared openly via public data repositories so that studies can be properly replicated and data used in future meta-analyses.

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Background: The state of Bihar has the third largest number of snakebite deaths in India. The purpose of this study is to explore the factors related to human-snake conflicts in northwest Bihar and southern Nepal. Using these findings, various strategies were proposed to reduce the incidence of snakebites. Method: Data were collected from 609 patients at Duncan Hospital in Raxaul, Bihar, India between 1 July 2012 and 30 June 2013. Patients were included if they had a history of snakebite or unknown bites. Patients with symptoms of envenomation but no known bites were also included, as were patients who were dead on arrival due to a snakebite. Results: The 10-19 year old age group is the peak age group (28.4%) for snakebite. There is a slight preponderance of males (52.7%). 51.4% of bites occurred on the foot/ankle. The envenomation rate was 12.6%. The mortality rate of those envenomed that arrived at the hospital alive was 6.3%. Fourteen people were dead on arrival at the hospital. 75% of people were unable to identify what, or what type of snake, bit them. Common Wolf Snakes (Lycodon aulicus) were the most common snakes brought to the hospital, followed by Spectacled Cobra (Naja naja). Patients who brought snakes to the hospital and attempted identification were all successful at identifying cobras, but all those who brought in Common Wolf Snakes incorrectly identified them as Kraits. The highest monthly frequency of snakebites occurred between June and September; while on a daily basis, the highest frequency occurred between 1700hrs-2200hrs, the time in which 39.1% of all bites occurred. 59.2% of the bites occurred in and around the house. Farming, housework, sleeping, playing, and toileting in fields were the activities most commonly occurring when bitten. Sleeping on the floor increased the risk of envenomation [OR= 5.8, 95%CI 1.8-18.6], while sleeping under a mosquito net decreased the risk of envenomation [OR= 0.17, 95%CI 0.04-0.6]. Conclusion: Snakebite is a rural hazard in Northern Bihar, not just an occupational hazard. Use of toilets and sleeping on beds with well tucked in mosquito nets may help prevent snakebites. Education to reduce the risk of snakebites should begin in childhood and be regularly reinforced prior to the rainy season. Prevention measures should include environmental management such as keeping eating areas clean and keeping food storage and sleeping areas a distance apart.

We provide a molecular phylogeny of Asian pit vipers (the genus Gloydius) based on four mitochondrial genes (12S, 16S, ND4, and cytb). Sequences of Gloydius himalayanus, the only member of the genus that occurs south of the Himalayan range, are included for the first time. In addition, two new species of the genus Gloydius are described based on specimens collected from Zayu, Tibet, west of the Nujiang River and Heishui, Sichuan, east of the Qinghai-Tibet Plateau. The new species, Gloydius lipipengi sp. nov., can be differentiated from its congeners by the combination of the following characters: the third supralabial not reaching the orbit (separated from it by a suborbital scale); wide, black-bordered greyish postorbital stripe extending from the posterior margin of the orbit (not separated by the postoculars, covering most of the anterior temporal scale) to the ventral surface of the neck; irregular black annular crossbands on the mid-body; 23-21-15 dorsal scales; 165 ventral scales, and 46 subcaudal scales. Gloydius swildsp. nov. can be differentiated from its congeners by the narrower postorbital stripe (only half the width of the anterior temporal scale, the lower edge is approximately straight and bordered with white); a pair of arched stripes on the occiput; lateral body lakes black spots; a pair of round spots on the parietal scales; 21 rows of mid-body dorsal scales; zigzag dark brown stripes on the dorsum; 168–170 ventral scales, and 43–46 subcaudal scales. The molecular phylogeny in this study supports the sister relationship between G. lipipengisp. nov. and G. rubromaculatus, another recently described species from the Qinghai-Tibet Plateau, more than 500 km away, and indicate the basal position of G. himalayanus within the genus and relatively distant relationship to its congeners.

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Green pit vipers are the largest group of venomous vipers in tropical and subtropical Asia, which are responsible for most of the bite cases across this region. Among the green pit vipers of the Indian subcontinent, Trimeresurus erythrurus is the most prevalent; however, limited knowledge is available about its venomics. Proteome decomplexation of T. erythrurus venom using mass spectrometry revealed a blend of 53 different proteins/peptides belonging to 10 snake venom protein families. Phospholipase A 2 and snake venom serine proteases were found to be the major enzymatic families, and Snaclec was the major nonenzymatic family in this venom. These protein families might be responsible for consumptive coagulopathy in victims. Along with these, snake venom metalloproteases, L-amino acid oxidases, disintegrins, and cysteine-rich secretory proteins were also found, which might be responsible for inducing painful edema, tissue necrosis, blistering, and defibrination in patients. Protein belonging to C-type lectins, C-type natriuretic peptides, and glutaminyl-peptide cyclotransfreases were also observed as trace proteins. The crude venom shows platelet aggregation in the absence of any agonist, suggesting their role in alterations in platelet functions. This study is the first proteomic analysis of T. erythrurus venom, contributing an overview of different snake venom proteins/peptides responsible for various pathophysiological disorders obtained in patients. Data are available via ProteomeXchange with the identifier PXD038311.