"As we've covered before, this is only a mystery if you are the worst detective ever. Croatan was the name of a nearby island populated by friendly Native Americans. In the years after the people of Roanoke "disappeared," genetically impossible Native Americans with gray eyes and an "astounding" familiarity with distinctly European customs began to pop up in the tribes that moved between Croatan and Roanoke islands."
Read more: http://www.cracked.com/article_1Infection
The virus is considered "demonic germ warfare", as it leaves traces of sulfur in the blood of the infected. One becomes infected by either direct exposure or from getting infected blood in an open wound. Within three hours of being exposed to the virus, infected will begin to show symptoms, which include enhanced speed and strength. The longer the infection is in the blood, the stronger and faster they become, making them more difficult to kill.
Often referred to as Croats or zombies, infected individuals seeks out any remaining living creatures to continue the spread of the virus. Similar to their undead counterparts, Croats are generally mindless and extremely violent, with one goal and one goal only: to infect everyone and wipe humanity off the planet.
There is no cure for the Croatoan Virus.
Once infected, the only way to stop a Croat is to kill it. The most efficient way to kill an infected individual is with a gunshot to either the heart or the head. Unlike zombies, Croats are more like living people with an intense case of rabies, and can be killed with ordinary weapons.