Assessment of snakebite burdens, clinical features of envenomation, and strategies to improve snakebite management in Vietnam

Highlights

• Snakebite is a serious health issue in Vietnam

• Epidemiological data and clinical features of snake envenomation in Vietnam is underreported.

• Epidemiology, clinical features, diagnosis and treatment of snakebite in different locales of Vietnam are highlighted.

• A roadmap to improve snakebite management in Vietnam is proposed.

Abstract

The sheer paucity of scientific documentation of herpetofauna in Vietnam and the rudimentary healthcare response to snakebite have stimulated this review. Over six decades of data culled from public data bases and search engines, have been used to assess snakebite burdens, clinical features of envenomation, and strategies for snakebite management in Vietnam. In addition, biochemical and proteomic analyses to decipher venom composition, rapid analytical techniques to be used for clinical diagnosis of snakebite in Vietnam have been discussed in detail. The assessment of efficacy, safety, and quality of commercial antivenom produced in Vietnam and improvement of antivenom production to meet the national requirement has been critically examined. It is apparent that snake bite incidence in Vietnam is exacerbated by mismatch in demand and supply of antivenom therapy, insufficient medical facilities, preference for traditional healers and poor management of clinical records. The impediments arising from geographical and species-specific variation in venom composition can be overcome by the ‘Omics approach’, and scientific documentation of pathophysiological manifestations post envenomation. The development of next generation of therapeutics, encouraging clinical research, novel approaches and social awareness against snakebite and its treatments have been suggested to significantly reduce the snakebite mortality and morbidity in this region.

Introduction

Snakebite is a calamity, particularly in the rural areas of tropical and sub-tropical countries, where the access to healthcare facilities is very limited. The World Health Organization (WHO) has declared snakebite a category A neglected tropical disease; galvanized by the sheer dearth of attention accorded to this deadly tropical disease (Chippaux, 2017). Globally, the highest incidence of snake bite is reported from Asia, with the South-east Asian countries being major contributors (Chippaux, 1998; Kasturiratne et al., 2008).

Vietnam in South-East Asia, with a land cover of 3, 10,000 km² and a population of 92 million, is a large repository of varied herpetofauna. Of the approximately 140 species of snakes found in Vietnam; 31 species are venomous, of which 18 species are terrestrial and 13 species are marine (Harding and Welch, 1980; Quyen, 2003). Reports of snakebite incidence date from the Vietnam War in 1950 and underscore the heightened fear and mortality it caused among the soldiers (Berlinger and Flowers, 1973; Guillemot, 2009). The medically important venomous snakes of Vietnam, responsible for fatal bites in this region are shown in Table 1. It is noteworthy that, snakebite burden in other south-east Asian countries like Thailand (Chanhome et al., 1998; Pochanugool et al., 1998; Viravan et al., 1992), Malaysia (Chew et al., 2011; Jamaiah et al., 2006),and Myanmar (Chippaux, 1998; Mahmood et al., 2018; Pe et al., 2006) are well documented. However, snakebite incidences in Vietnam are neither globally or nationally comprehensively surveyed (Quyen, 2003). Only a few hospital-based data on snakebite in Vietnam are readily available (Blessmann et al., 2018; Eriksson, 2011; Eriksson and Nguyen, 2017; Quyen, 2003; Thang et al., 2020). The exact magnitude of the public-health calamity posed by snakebites in Vietnam is yet to be determined, which makes it difficult for public-health officials and policy makers to set up an appropriate framework for prevention and control of snakebite.

In this article, we have presented a comprehensive review and critical analysis of the burden and clinical features of snakebite, geographical variation of venom composition of medically important snakes, availability of antivenom, and management of snakebite in Vietnam by sifting through the literature available in public databases (Scopus, web of science, Pubmed, google scholar) covering the period from 1954 to 2020. We have also used the google search engine by employing key words; ‘snakebite in Vietnam’, ‘clinical report of snakebite in Vietnam’, 'snake venom characterization from Vietnam’ ‘epidemiological study of snakebite in Vietnam’; the search included sources in both English and Vietnamese.