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The distribution of Daboia russelii. The Indian subcontinent distribution is not as continuous as the stylized diagram suggests (particularly in the Ganges delta). In the inset of the Lesser Sundas, there are records from East Java (EJ), Komodo (K), Flores (F), Solor (S), Adonara (A) and Lembata (L).
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The Russell's viper complex has a patchy (relict) distribution over large areas of Asia from Pakistan to Taiwan and the Lesser Sunda islands. In many areas it is the primary cause of snakebite mortality, and hence a serious medical problem. A multigene mitochondrial gene tree, supported by multivariate morphometry and basic colour pattern, suggests...
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Background: In a predominantly agricultural country like India, with rich in flora and fauna, long rainy season and rural background, the encounter between man and snake is a frequent occurrence. Viper-bites are more common than other poisonous snakebites. Only the cases of snakebite with severe envenomation reach the health care centers. This stud...
Snakebite envenoming (SBE) predominantly affects rural impoverished communities that have limited access to immediate healthcare. These communities often hold numerous myths/misbeliefs about snakes and SBE. Moreover, healthcare professionals who practice in rural regions often work in unstable situations with limited medical infrastructure and ther...
Background
Snakebite incidence shows both spatial and temporal variation. However, no study has evaluated spatiotemporal patterns of snakebites across a country or region in detail. We used a nationally representative population sample to evaluate spatiotemporal patterns of snakebite in Sri Lanka.
Methodology
We conducted a community-based cross-s...
Snakebite envenoming is a serious medical problem in different areas of the world. In Latin America, the major prevalence is due to snakes of the family Viperidae, where rattlesnakes (Crotalus) are included. They produce hemotoxic venom which causes bleeding, tissue degradation and necrosis. Each venom has several enzymatic activities, producing di...
Snakebite is a serious occupational hazard affecting mainly rural populations of tropical and subtropical developing countries. Lachesis muta (Bushmaster) bites are extremely serious but are rarely reported in the literature. Bushmaster envenomings are characterized by intense local pain, edema, neurotoxicity, hypotension, local hemorrhage, and dra...
Citations
... The species has been systematically grouped into five subspecies, each differentiated by variation in body colouration and markings: (1) Daboia russelii (found in India, Pakistan, Nepal, and Bangladesh); (2) Daboia russelii pulchella (native to Sri Lanka); (3) Daboia russelii siamensis (distributed in Thailand, Myanmar, and China); (4) Daboia russelii formosensis (located in Taiwan); and (5) Daboia russelii limitis (identified in Indonesia) (Warrell 1989). However, through a detailed investigation of morphological features and mitochondrial DNA, Thorpe and group categorized Russell's vipers into two distinct species: Daboia russelii (found in the west of the Bay of Bengal) and Daboia siamensis (found in the east of the Bay of Bengal) (Thorpe et al. 2007). Daboia russelii encompasses species found across India, Sri Lanka, Pakistan, and Bangladesh, while Daboia siamensis includes species inhabiting southern China, Taiwan, and Indonesia. ...
Snakebite envenomation is a serious health concern in tropical regions, resulting in high mortality. The World Health Organization (WHO) has declared it a neglected tropical disease and is working on strategies to reduce mortality. Russell’s viper (Daboia russelii) is one of the most abundant venomous snakes found across Southeast Asia. Proteomic analysis of Russell’s viper venom has demonstrated variation, with phospholipase A2 (PLA2) being the most abundant toxin across geographic boundaries. PLA2, a major constituent of the low-molecular-weight fraction of snake venom, hydrolyses phospholipids at the sn-2 position, releasing arachidonic acid and lysophospholipids. They are reported to cause various pharmacological effects, including hemolysis, anticoagulation, neurotoxicity, myotoxicity, and oedema. Though administration of antivenoms (ASV) is the primary treatment for envenomation, it has many drawbacks. Besides causing hypersensitivity reactions and life-threatening anaphylaxis, treatment with ASV is further complicated due to its inability to neutralize low-molecular-weight toxins. Thus, there is a greater need to produce next-generation antivenoms that can target specific toxins in the venom. In this review, we explored the classification of Russell’s viper and the variation in its proteomic profile across Southeast Asia to date. In addition, we have also summarized the mechanism of action of PLA2 and discussed various isoforms of PLA2 found across different regions with their respective pharmacological effects. Finally, the drawbacks of commercially available antivenoms and the molecules investigated for inhibiting the low-molecular-weight toxin, PLA2 are discussed.
... The current taxonomy of Daboia russelii is a result of the integration of morphological studies of several authors including Smith (1917;1943), Deraniyagala (1955) and Wüster et al., (1992), molecular genetic studies including that of Thorpe et al., (2007) and ...
... June 2024 Journal of the National Science Foundation of Sri Lanka 52 (2) information on envenomation symptoms (Warrell, 1989). The latest update on its classification includes two species, namely, Daboia russelii (West of the Bay of Bengal) to which the Sri Lankan haplotype belongs, and Daboia siamensis (East of the Bay of Bengal) (Wüster et al., 1992;Thorpe et al., 2007). Because a synonymous nomen Daboia pulchella (Gray, 1842) originating from Sri Lanka is present, Thorpe et al., (2007) rightly included Sri Lankan population sequences too. ...
... The latest update on its classification includes two species, namely, Daboia russelii (West of the Bay of Bengal) to which the Sri Lankan haplotype belongs, and Daboia siamensis (East of the Bay of Bengal) (Wüster et al., 1992;Thorpe et al., 2007). Because a synonymous nomen Daboia pulchella (Gray, 1842) originating from Sri Lanka is present, Thorpe et al., (2007) rightly included Sri Lankan population sequences too. The sequence was sourced from Gampola, a wet zone place in Sri Lanka known for its biotic distinction from the Indian mainland (Gunawardene et al., 2007). ...
The Russell's viper (Daboia russelii) is a medically important viper found in South Asia, including Sri Lanka. This study focused on the phylogeny of Russell's vipers in the geographically segregated coastal peninsula of Jaffna, Sri Lanka. The study aimed to find out whether the specimens collected in Jaffna are different from previously reported forms since such an investigation has not been carried out so far specifically in this area, and to find out whether geographical segregation has had an impact on it. We obtained mtDNA sequences of samples representing six geographical locations in the Jaffna peninsula for the mitochondrial protein-coding genes Cytb(576bp) and ND2(270bp). Our molecular analyses recovered two distinct clades: D. russelii and D. siamensis. The clade of D. russelii comprises two sister lineages, Pakistan and India/Sri Lanka. The uncorrected pairwise Cytb genetic distance between the species range from 5.0 to 14.5 percent. The current study confirms a sister group relationship between the Indian/Sri Lankan lineage and the Pakistani lineage of the Russell's viper (D. russelii). Additionally, it discloses the presence of an incipient genetic divergence between Russell's viper populations in Jaffna and South India.
... A value of 0.550 or less is classed as low human development, 0.550-0.699 is medium, 0.700-0.799 is high and 0.800 or greater is very high [15]. All six of the significant threat examples occur in at least one low-ranking country: Anopheles gambiae, feral dog, Lutzomyia longipalpis, Russell's viper (Daboia russelii), Schistosoma spp., and Triatoma infestans [16,17,18,19,20,21]. There seems to be a much higher occurrence of species considered significant threats in less developed countries compared to countries that are more developed and therefore score higher on the HDI. ...
Throughout our history, humanity and the kingdom Animalia have been in conflicts with both sides sharing countless casualties as the outcome. Among animals, adult female mosquitoes of the Anopheles genus are infamously labelled the deadliest to humans in terms of the number of deaths they cause each year. In this scientific paper, an analysis is given over what other direct and indirect factors can be considered when classifying a species of animal as 'dangerous'. It discusses and concludes exactly why they make it more of a danger to human health and safety than others. This is done utilising a brand-new, categoric scale — which has been dubbed the "Crespo scale" — created and designed to categorise all animal species from categories 1–5. One posing the least danger and five the most. The categorisation is performed by examining factors relevant to the animals themselves, which include the estimated Population Size (PS) and Mortality Rate (MR). The hypothesis is that species possessing a larger PS and a higher MR will be placed further up on the scale and thus are more likely to be a threat. Ultimately, both PS and MR are quantifiable factors that can be used to measure and categorise a species' level of danger in a less biased and more accurate, consistent way. However, the factor of MR can often be indirectly influenced by human-related factors that apply to the human development of a country and its general populace.
... Genus Vipera is widespread throughout Western and Central Asia. It is a genus in constant revision and recognizes some two dozen species and a number of subspecies (Stümpel and Joger, 2009;Thorpe et al, 2007). The genus Macrovipera extends from Eastern Europe to Western and Central Asia, as well as Mediterranean Africa (David and Ineich, 1999). ...
Journal of the Egyptian Society of Parasitology, Vol. 54, No. 1, April 2024
J. Egypt. Soc. Parasitol. (JESP), 54(1), 2024: 137 - 142
Abstract
An extensive study of neutralization of lethality of two species of elapid, seven species of
genus Viper, and two species of Macrovipera by VACSERA polyvalent snake antisera.
The results showed that polyvalent snake venom antisera prepared by injecting horses with
Naja haje, Naja nigricolis, and Cerrastes cerrastes venom) was highly effective in neutraliz�ing the venoms specifically and neutralized Para-specifically others including Vipera palasti�nae, Vipera xanthina, Vipera ammodytes, Echis coloratus, Echis carinatus, Cerastes vipera
and pseudocerrastes-feildi beside Macrovipera species including Macrovipera lebetina ob�tuse, M. lebetina turanica.
Key words: Egypt, VACSERA polyvalent snake, Africa, Middle East, Snake venom
... Presence of a large number of proteins belonging to these families probably contributes to the haemotoxic nature of the venom. Besides, they might be responsible for the classical symptoms observed post Daboia russelii envenomation such as haemostatic disturbances leading to spontaneous bleeding and painful progressive swelling (Thorpe et al., 2007;Management of Snakebite, 2017). On the other hand, the trace families detected were KSPI, Disintegrin, VEGF, VNGF, LAAO and GPC. ...
... The differences in venom composition cited by Shi et al. concern comparisons between populations from Rajasthan and Gujarat and those from Sri Lanka (Sintiprungrat et al. 2016), again leaving an enormous sampling gap. Venom composition is often a poor predictor of taxonomic affinities (Strickland et al. 2018;Thorpe et al. 2007), with startling differences in composition over tens of kilometres persisting even in the face of unrestricted gene flow within continuously distributed species (Zancolli et al. 2019). Moreover, extensive differences in venom composition among populations of Naja naja within India have also been documented (Deka et al. 2023;Saikumari et al. 2015;Senji Laxme et al. 2021;Shashidharamurthy & Kemparaju 2007), undermining the case for venom composition as supporting a mainland-Sri Lanka split in N. naja. ...
In response to the recent in passing ("en passant") taxonomic decision to split Naja naja (Linnaeus) and recognise the Sri Lankan populations as a separate species, N. polyocellata Deraniyagala, we analyse the evidence underlying the proposal and its nomenclatural implications. The proposed split is weakly supported by the available evidence, so that retaining N. naja as a single species seems appropriate until further analysis. Moreover, the proposal raises several issues concerning types, type locality and nomenclature. Linnaeus' description of Coluber naja was based on a single preserved specimen seen by him (now lost) and several illustrations in Seba's Thesaurus. The specimens that were the basis of these illustrations constitute part of the type series. Two of the latter specimens, ZMB 2795 and 2796, have been rediscovered in the collections of the Museum für Naturkunde, Berlin. Here, we describe them, and determine that both are of Sri Lankan origin. To settle the question of the type and type locality of this iconic taxon, we designate ZMB 2796 as lectotype for the species, thereby implicitly restricting the type locality to Sri Lanka. The name "polyocellata" thus becomes a subjective junior synonym of Coluber naja, and the name Naja brasiliensis Laurenti, 1768 an objective junior synonym thereof. Any taxonomic recognition of additional diversity within N. naja would thus require the renaming of Indian, not Sri Lankan spectacled cobras, but should await a significant body of convincing evidence. We caution against taxonomic decisions taken "in passing", based on limited evidence and without in-depth assessment of their nomenclatural implications.
... Russell's viper is a widespread species found in South and Southeast Asia, as well as China. Based on previous molecular [1] and morphological [2] studies, the Daboia genus has been divided into two well-defined taxa: D. russelii (west of the Bengal Bay) and D. siamensis (east of the Bengal Bay). The species designation and regional distribution align with variations observed in the clinical features of Russell's viper envenomation [2,3]. ...
The Russell’s viper (Daboia siamensis) is a medically important venomous snake in
Myanmar. Next-generation sequencing (NGS) shows potential to investigate the venomcomplexity, giving deeper insights into snakebite pathogenesis and possible drug discoveries.mRNA from venom gland tissue was extracted and sequenced on the Illumina HiSeq platform andde novo assembled by Trinity. The candidate toxin genes were identified via the Venomix pipeline.Protein sequences of identified toxin candidates were compared with the previously describedvenom proteins using Clustal Omega to assess the positional homology among candidates.
Candidate venom transcripts were classified into 23 toxin gene families including 53 unique full-length transcripts. C-type lectins (CTLs) were the most highly expressed, followed by Kunitz-typeserine protease inhibitors, disintegrins and Bradykinin potentiating peptide/C-type natriuretic peptide (BPP-CNP) precursors. Phospholipase A 2 , snake venom serine proteases,metalloproteinases, vascular endothelial growth factors, L-amino acid oxidases and cysteine-rich secretory proteins were under-represented within the transcriptomes. Several isoforms of
transcripts which had not been previously reported in this species were discovered and described.Myanmar Russell’s viper venom glands displayed unique sex-specific transcriptome profiles whichwere correlated with clinical manifestation of
envenoming. Our results show that NGS is a useful tool to comprehensively examine understudied venomous snakes.
... Epidemiological studies have identified Russell's viper (Daboia russelii) as being the main perpetrator responsible for most bites (Vaiyapuri et al., 2013;Samuel et al., 2020). The clinical manifestations of Russell's viper envenomations display significant variations (Thorpe et al., 2007;Adhikari et al., 2019), while most patients manifest typical features, predominantly composed of local tissue damage, coagulopathies, nephrotoxicity and neurotoxicity, other victims also present various rare pathological complications such as Wunderlich syndrome (spontaneous non-traumatic renal haemorrhage) (Senthilkumaran et al., 2022a), priapism (prolonged penile erection) (Senthilkumaran et al., 2021b), salivary calculus development in the salivary glands (Arathisenthil et al., 2022) and splenic rupture (Senthilkumaran et al., 2021a). A better understanding and broader knowledge surrounding the clinical manifestations of SBE in patients is crucial for medical practitioners to identify such rare complications and mitigate unfavourable outcomes. ...
The clinical management of snakebite envenomation (SBE) is challenging in many tropical and subtropical regions of developing countries due to the complex clinical manifestations and inadequate medical infrastructure. Some venomous snakes, such as the Indian Russell's viper (Daboia russelii) cause a wide range of rare complications in addition to their classical envenomation effects. In general, these uncommon complications are often misdiagnosed or not treated promptly due to a lack of awareness about these conditions. Thus, it is critical to report such complications to draw the attention of the healthcare and research communities to improve the clinical management and scientific research of SBE, respectively. Here, we report bilateral adrenal and pituitary haemorrhages in an SBE patient following a bite by Russell's viper in India. The initial symptoms included gum bleeding, swelling, axillary lymphadenopathy and clotting abnormality. Despite the administration of antivenom, the patient presented palpitation, nausea, and abdominal pain, which were not recovered by combinational therapy with epinephrine and dexamethasone. Further infusion of antivenom did not address these issues and the patient displayed persistent hypotension, hypoglycaemia and hyperkalaemia suggesting an adrenal crisis. Inadequate secretion of corticosteroids was confirmed by laboratory tests, and imaging investigations revealed haemorrhages in both the adrenal and pituitary glands. The patient made a full recovery after treatment with hydrocortisone and thyroxine. This report adds to the growing evidence of rare complications induced by Russell's viper envenomations and it provides relevant guidance to diagnose and treat such complications in SBE victims.
... Moreover, recent phylogeographical and molecular studies have refined our understanding of cryptic speciation across biogeographic boundaries or within biogeographic regions 15,16 , and even propounded the suitability of reptiles in particular as biogeographic indicators 17,18 . Recent studies focussing on widespread reptilian species have also established the existence of previously unnoticed cryptic diversity, including in lizards 19-22 and snakes [23][24][25][26][27][28][29][30] . ...
The banded krait, Bungarusfasciatus is a widespread elapid snake, likely to comprise several distinct species in different geographic regions of Asia. Therefore, based on molecular phylogenetics and comparative morphology data, we present an overview of the systematic composition of the species to delimit potential biogeographic boundaries. Our phylogenetic analyses, based on four mitochondrial genes, reveal the existence of at least three evolutionary lineages within B.fasciatus, corresponding to Indo-Myanmar, Sundaic and eastern Asian lineages. We are convinced that there are at least three taxonomic entities within the nomen B.fasciatus and restrict the distribution of B.fasciatus sensu stricto to the Indo-Myanmar region. We also provide additional natural history data of the taxon from eastern India. Finally, we advocate further studies to establish the degree of reproductive isolation among these diverging evolutionary lineages and to reassess the systematic status of this species complex especially the Sundaic and eastern Asian lineages.
... The Russell's viper (Daboia siamensis) has a vast but disjointed distribution across many regions of South and South-East Asia. It is found in parts of Pakistan, India, Bangladesh and Sri Lanka and, further east, in Taiwan, Thailand, Indonesia and Mainland China [1,2]. Across this distribution, D. siamensis is responsible for a large number of envenomings, which can result in marked local and systemic injuries in envenomed humans [3][4][5][6][7]. ...
The venom of the Russell’s viper (Daboia siamensis) contains neurotoxic and myotoxic phospholipase A2 toxins which can cause irreversible damage to motor nerve terminals. Due to the time delay between envenoming and antivenom administration, antivenoms may have limited efficacy against some of these venom components. Hence, there is a need for adjunct treatments to circumvent these limitations. In this study, we examined the efficacy of Chinese D. siamensis antivenom alone, and in combination with a PLA2 inhibitor, Varespladib, in reversing the in vitro neuromuscular blockade in the chick biventer cervicis nerve-muscle preparation. Pre-synaptic neurotoxicity and myotoxicity were not reversed by the addition of Chinese D. siamensis antivenom 30 or 60 min after venom (10 µg/mL). The prior addition of Varespladib prevented the neurotoxic and myotoxic activity of venom (10 µg/mL) and was also able to prevent further reductions in neuromuscular block and muscle twitches when added 60 min after venom. The addition of the combination of Varespladib and antivenom 60 min after venom failed to produce further improvements than Varespladib alone. This demonstrates that the window of time in which antivenom remains effective is relatively short compared to Varespladib and small-molecule inhibitors may be effective in abrogating some activities of Chinese D. siamensis venom.