Maul by Tricia Sullivan
My rating: 4 of 5 stars
Summary: In a mall like any other, two gangs of teenaged girls are about to embark on an orgy of shopping and designer violence. In the battleground of cool, they'll fight for their lives to prove that "image is everything." And in another place, within a sealed room, a lone man fights an equally desperate war against a new virus and the scientists who have developed it. If anyone gets out alive, it will be a small miracle.