Which snakes are the leading contributor to snakebite injuries in North America?

Rattlesnakes are a group of venomous snakes of the genera 'Crotalus' and 'Sistrurus' of the subfamily 'Crotalinae' (the pit vipers). All rattlesnakes are vipers. Rattlesnakes receive their name from the rattle located at the end of their tails, which makes a loud rattling noise when vibrated. This noise deters the predators or serves as a warning to passers-by.

Rattlesnakes are the leading contributor to snakebite injuries in North America, but they rarely bite unless provoked or threatened. Their bites, if treated promptly, are seldom fatal. In the U.S., the approved antivenom, including for the pit viper (rattlesnake, copperhead, and water moccasin) snakebite, is based on a purified product made in sheep known as CroFab. It was approved by the FDA (The United States Food and Drug Administration) in October 2000. The majority of antivenoms (including all snake antivenoms) are administered intravenously.