That is a coral snake . Check out this portion from the Wikipedia entry:
New World coral snakes possess the second most potent venom of any North American snake
Unfortunately, it also says:
The sole manufacturer of Eastern and Texas Coral Snake Antivenom, Wyeth, has ceased production of this product and it is estimated that all remaining in-date stocks of Coral Snake Antivenom in the United States will be exhausted between October and December, 2008
Absent the antivenom (emphasis mine),
Victims of Eastern and Texas Coral snakebite should be transported as soon as possible to a tertiary level hospital which can provide constant monitoring of neurological and respiratory symptoms for 24 hours or more and if these symptoms occur be ready and able to sedate, endotracheally intubate and mechanically ventilate such patients for up to a week or until neurological and respiratory paralysis resolves.