injuries poisoning
Snakebites
Introduction
Of about 3000 snake species throughout the world, only about 15% worldwide and 20% in the US are dangerous to humans because of venom or toxic salivary secretions (see table). At least one species of venomous snake is native to every state in the US except Alaska, Maine, and Hawaii. Almost all are crotalines (also called pit vipers because of pitlike depressions on either side of the head, which are heat-sensing organs): Rattlesnakes Copperheads Cottonmouths (water moccasins) More than 60,000 bites and stings are reported to poison centers and result in about 100 deaths each year in the US. About 45,000 are snakebites (of which 7000 to 8000 are venomous and cause about 5 deaths). Rattlesnakes account for the majority of snakebites and almost all deaths. Copperheads and, to a lesser extent, cottonmouths account for most other venomous bites. Coral snakes (elapids) and imported species (in zoos, schools, snake farms, and amateur and professional collections) account for<1% of all bites. Most patients are males between 17 and 27 years; 50% of them are intoxicated and deliberately handled or molested the snake. Most bites occur on the upper extremities. Five or 6 deaths occur annually in the US. Risk factors for death include age extremes, handling of captive snakes (rather than wild encounters), delay in treatment, and undertreatment. Outside the US, fatal snakebites are much more common, accounting for>100,000 deaths yearly. 