Morbidity, Disability and Mortality Due to Snakebite Envenoming

Snakebite envenoming is a potentially life-threatening disease that typically results from the 2. injection of a mixture of different toxins (“venom”) following the bite of a venomous snake. Envenoming can also be caused by venom being sprayed into a person’s eyes by certain species of snakes that have the ability to spit venom as a defence measure. Not all snakebites result in envenoming: some snakes are non-venomous and venomous snakes do not always inject venom during a bite. About 50–55% of all snakebites result in envenoming. Snake venoms are complex mixtures of protein and peptide toxins, varying from one species to another, and even within species. The toxins in snake venoms are evolutionarily adapted to interact with a large variety of cellular targets in the organisms exposed to them. In humans and animals, snakebite envenoming affects multiple organ systems (depending on the particular species of snake and the classes of toxins present in the venom) and can cause, among other things: haemorrhage and prolonged disruption of haemostasis, neuromuscular paralysis, tissue necrosis, myolysis (muscle degeneration), cardiotoxicity, acute kidney injury, thrombosis and hypovolaemic shock.