Kraits of Indian subcontinent: Natural history, risks, venom variation, lethality and treatment strategies - A comprehensive review

Abstract

The World Health Organization (WHO) has re-classified "Snakebite" as a Neglected Tropical Disease in 2017, and estimated that as many as 5.4 million people suffer from snakebites every year. Out of this large number of snakebites, envenoming occurs in about 50 % of the cases, and the number of resulting deaths could be as high as 138,000. The genus Bungarus commonly known as kraits are medically important elapid snakes widely distributed in the Indian subcontinent, southern China and the Southeast Asian countries (except Philippines). The Indian subcontinent (India, Bangladesh, Bhutan, Nepal, Pakistan, Sri Lanka and Maldives) is home to 8-9 krait species, among which B. caeruleus and B. niger are highly venomous. This review presents the current state of knowledge on krait bites in the Indian subcontinent. The risk of envenomation by kraits, the venom lethality and krait bite management in the Indian subcontinent have been critically analyzed. Moreover, the issue of dry bites from kraits and their management has also been reviewed. Furthermore, critical aspects, such as knowledge of snakebite management among healthcare workers, clinical symptoms of snakebite patients, and treatment in healthcare facilities including antivenom administration and their clinical efficacy, have helped us in identifying the critical knowledge gaps. Proposed preventive measures will help to reduce krait bite associated mortality and morbidity. Moreover, development and accessibility to affordable treatment options may help in the effective management of krait bites.

Keywords: Antivenom; Bungarus; Envenomation; Indian subcontinent; Kraits; Neurotoxicity.