Pre-clinical assays predict pan-African Echis viper efficacy for a species-specific antivenom.

Snakebite is a significant cause of death and disability in subsistent farming populations of sub-Saharan Africa. Antivenom is the most effective treatment of envenoming and is manufactured from IgG of venom-immunised horses/sheep but, because of complex fiscal reasons, there is a paucity of antivenom in sub-Saharan Africa. To address the plight of thousands of snakebite victims in savannah Nigeria, the EchiTAb Study Group organised the production, testing and delivery of antivenoms designed to treat envenoming by the most medically-important snakes in the region. The Echis saw-scaled vipers have a wide African distribution and medical importance. In an effort to maximise the clinical utility of scarce antivenom resources in Africa, we aimed to ascertain, at the pre-clinical level, to what extent the E. ocellatus-specific EchiTAbG antivenom, which was designed specifically for Nigeria, neutralised the lethal activity of venom from two other African species, E. pyramidum leakeyi and E. coloratus.
Despite apparently quite distinctive venom protein profiles, we observed extensive cross-species similarity in the immuno-reactivity profiles of Echis species-specific antisera. Using WHO standard pre-clinical in vivo tests, we determined that the monospecific EchiTAbG antivenom was as effective at neutralising the venom-induced lethal effects of E. pyramidum leakeyi and E. coloratus as it was against E. ocellatus venom. Under the restricted conditions of this assay, the antivenom was ineffective against the lethal effects of venom from the non-African Echis species, E. carinatus sochureki.
Using WHO-recommended pre-clinical tests we have demonstrated that the new anti-E. ocellatus monospecific antivenom EchiTAbG, developed in response to the considerable snakebite-induced mortality and morbidity in Nigeria, neutralised the lethal effects of venoms from Echis species representing each taxonomic group of this genus in Africa. This suggests that this monospecific antivenom has potential to treat envenoming by most, perhaps all, African Echis species.
AuthorsNicholas R Casewell, Darren A N Cook, Simon C Wagstaff, Abdulsalami Nasidi, Nandul Durfa, Wolfgang Wüster, Robert A Harrison
JournalPLoS neglected tropical diseases (PLoS Negl Trop Dis) Vol. 4 Issue 10 Pg. e851 ( 2010) ISSN: 1935-2735 [Electronic] United States
PMID21049058 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Antibodies, Neutralizing
  • Antivenins
  • Viper Venoms
  • Africa South of the Sahara
  • Animals
  • Antibodies, Neutralizing (immunology, pharmacology)
  • Antivenins (immunology, pharmacology)
  • Disease Models, Animal
  • Drug Evaluation, Preclinical
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoblotting
  • Mice
  • Neutralization Tests
  • Snake Bites (therapy)
  • Survival Analysis
  • Viper Venoms (antagonists & inhibitors, immunology)
  • Viperidae

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: