Venomous (DVD, 2004, Sensormatic)

A small town is eperiencing an abnormal number of gruesome deaths. It is only a matter of time before it becomes obvious that the victims have been attacked by genetically engineered rattlesnakes from a local experiment that went awry. The bitten are quarantined by the United States Army before an assault on the deadly giant snakes is carried out. As the virus from the bites spreads and the town is under siege the military takes one last stand to stop the evil rattlers from moving on and making the next town over its next set of victims.