Twisted Retribution

The world we once knew had changed in an unexpected way. Fifteen years ago when the meteor shower had struck the earth, the population of the world had become infected with a parasite. Everyone became the infected, and they roamed the earth looking for another living person or animal to infect. A team of survivors that were military fought their way to salvation, but when three of their own team members are bitten, two of them start mutating and they see that the parasite is evolving.... an alien species that wanted to take over the world. The other was not effected in the same way, it was different. Can the surviving team stop their mutated friends from carrying out the parasites plan? What did this mean for the one that was not infected after she was attacked?