Development of simple standard assay procedures for the characterization of snake venom.

In accordance with the recommendations of the report of a WHO Coordination Meeting on Venoms and Antivenoms, methods have been developed for the assessment of lethal, defibrinogenating, procoagulant, haemorrhagic, and necrotizing properties of venoms, and used to study 53 venoms from 30 different species of snakes of medical importance throughout the world. The venoms studied included Echis carinatus (Iran), Naja naja kaouthia (Thailand), Notechis scutatus (Australia), Trimeresurus flavoviridis (Japan), Vipera russelli (Thailand), and Crotalus atrox (USA), which comprise six of the eight venoms designated by WHO as international reference venoms (IRVs). (C. atrox venom replaced C. adamanteus venom, as an adequate supply of the latter was not available.) The tests used were simple and should be reproducible in other laboratories throughout the world. Procedures for assaying neuromuscular paralytic activity and systemic myotoxic activity have yet to be developed.The tests will be used to assay the neutralizing potency of both international standard antivenoms (raised using the IRVs) and new and currently available commercial antivenoms. Such studies should result in the production of more potent antivenoms for use in both developing and developed countries, and improve the understanding and management of snake bite throughout the world.