<P> Rattlesnakes tend to avoid wide - open spaces where they cannot hide from predators, and generally avoid humans if they are aware of their approach . Rattlesnakes rarely bite unless they feel threatened or provoked . A majority of victims (about 72%) are males, often young and intoxicated . Around half of bites occur in cases where the victim saw the snake, yet made no effort to move away . </P> <P> Caution is advised even when snakes are believed to be dead; rattlesnake heads can see, flick the tongue, and inflict venomous bites for up to an hour after being severed from the body . </P> <P> An estimated 7,000 to 8,000 people are bitten by venomous snakes in the United States each year, with about five deaths . The most important factor in survival following a severe envenomation is the time elapsed between the bite and treatment . Most deaths occur between six and 48 hours after the bite . If antivenom treatment is given within two hours of the bite, the probability of recovery is greater than 99% . </P> <P> When a bite occurs, the amount of venom injected is under voluntary control by the snake . The amount released depends on a variety of factors, including the condition of the snake (e.g., having long, healthy fangs and a full venom sack) and its temperament (an angry, hungry snake that has just been stepped on vs. a satiated snake that was merely surprised by walking near it). About 20% of bites result in no envenomation at all . A lack of burning pain and edema ⁄ in (1 cm) away from the fang marks after one hour suggests either no or minimal envenomation occurred . A lack of edema or erythema in the area of the bite after eight hours indicates a lack of envenomation for most rattlesnake bites . </P>

How fast can you die from a rattlesnake bite