Spectacled Cobra, Naja naja
Russell's Viper, Daboia russelii
Saw Scaled Viper, Echis carinatus
Hump-nosed Viper, Hypnale hypnale
AVRI is collaborating with Instituto Clodomiro Picado (ICP) of the University of Costa Rica and the University of Peradeniya, Sri Lanka, (UOP) to develop a geographic regional and species specific snake antivenom for Sri Lanka.
ICP is generously donating their time and resources to formulate an antivenom, from Sri Lankan snakes, with venom provided by AVRI. When the antivenom has been proven effective in pre clinical studies, the finished product will be presented to UOP where the clinical trials will be implemented, coordinated and monitored. When complete, this international collaborative effort will result in the provision of a much needed remedy for venomous snakebite that will save countless numbers of lives.
Snakebite in Sri Lanka
The island nation of Sri Lanka, in Southeast Asia, has one of the highest snakebite morbidity and mortality rates in the world. With a population of 20 million, approximately 40,000 people are bitten by snakes every year.
Available data place the snakebite mortality rate in Sri Lanka anywhere between 6 and 18 per 100,000 in population. Under-reporting of deaths due to snakebite is problematic. Many individuals living in rural areas, where there are more problems with snakebite and limited access to biomedical care, never make it to a hospital or choose to seek alternative forms of treatment through traditional healers. There are many reasons for the high mortality rates due to snakebite in Sri Lanka, including: 1) the absence of an effective geographic regional, species-specific antivenom for Sri Lankan snake species; 2) inordinately high incidence of adverse reactions caused from using high doses of the ineffective antivenoms available; 3) the presence of multiple highly venomous species from both Viperidae and Elapidae families responsible for the most medically significant envenomations; and 4) delay in time to appropriate hospital treatment.
Antivenoms presently available in Sri Lanka are purchased from India and developed using venoms from snake species native to, and collected in, India. Thus, these Indian produced antivenoms are non-specific to many venom components of Sri Lankan snakes of the same species. Furthermore, they are manufactured under conditions of questionable quality control.
Three to eight times more Indian produced antivenom has been required to treat a patient in Sri Lanka than in India, bitten by the same species of snake, to achieve only marginal results. Reactions to antivenom therapy have been recorded in as high as 80% of snakebite victims in Sri Lanka. The severity of these reactions has been correlated to the volume of antivenom administered. Five species of medical significance found on the island are the Russell’s viper, Daboia russelii, Spectacled cobra, Naja naja, Common krait, Bungarus caeruleus, Hump-nosed viper, Hypnale hypnale, and the Saw Scaled viper, Echis carinatus. Of the deaths attributed to snakebite, the majority are caused by D. russelii, followed by N. naja. and B. caeruleus respectively. H. hypnale, while rarely responsible for deaths, inflicts the greatest number of bites causing high morbidity resulting in hospitalization. Little is known about the effects of E. carinatus bites in Sri Lanka.
With Sri Lanka as the starting point, AVRI's objective is to reach into areas of the world suffering from the worst morbidity and mortality rates due to animal envenomations. The technology exists to improve pharmacotherapies, treatment protocols and quality of care within these regions.