COMMON KRAIT
The common krait (Bungarus caeruleus) is often considered to be the most dangerous snake species in India. Its venom consists mostly of powerful neurotoxins which induce muscle paralysis. Clinically, its venom contains presynaptic and postsynaptic neurotoxins,[72] which generally affect the nerve endings near the synaptic cleft of the brain. Due to the fact that krait venom contains many presynaptic neurotoxins, patients bitten will often not respond to antivenom because once paralysis has developed it is not reversible.[73] This species causes an estimated 10,000 fatalities per year in India alone.[71] There is a 70-80% mortality rate in cases where there is no treatment or poor and ineffective treatment (e.g., no use of mechanical ventilation, low quantities of antivenom, poor management of possible infection). Average venom yield per bite is 10 mg (Brown, 1973), 8 to 20 mg (dry weight) (U.S. Dept. Navy, 1968), and 8 to 12 mg (dry weight) (Minton, 1974).[72] The lethal adult human dose is 2.5 mg.[74][73] In mice, the LD50 values of its venom are 0.365 mg/kg SC, 0.169 mg/kg IV and 0.089 mg/kg .