Development of chicken egg yolk antibodies (IgY) against venom of cobra (Naja naja) and krait (Bungarus caeruleus) and a study on its neutralization potential

The Big Four snakes are the leading causes of snakebite mortality in India. Among them, The Indian spectacled cobra (Naja naja) and common krait (Bungarus caeruleus) contribute about one-third of the deaths. The conventional anti-snake venoms (ASV) produced from equine serum are found to be expensive, with a high frequency of clinical side effects, low specificity, and production drawbacks. The current study, therefore, attempted to develop chicken egg yolk immunoglobulins (IgY) as antivenoms against the venoms of cobra and krait venoms. The major pathophysiological properties of the venoms and the efficacy of monovalent ASV IgY were evaluated. The titer of anti-cobra and anti-krait IgY was found to be 1:64000 on the 145th day post-immunization. The results showed that venoms (lethal doses (LD50): cobra:0.375 mg/kg, krait:0.0375 mg/kg of mice) had hemolytic, pro-coagulant, inflammatory, hemorrhagic, and edematic activities that were effectively neutralized by ASV-IgY. 1 mL of monovalent ASV IgY was able to neutralize 0.22 mg of cobra venom and 0.028 mg of krait venom whereas 1 mL of commercial polyvalent antivenom was able to neutralize 0.28 mg of cobra venom and 0.035 mg of krait venom. The study results suggest that using chicken IgY as an monovalent antivenom could effectively treat snakebites.