A member of the S.T.A.R.S.Exeter branch of Maine. She participated in the raid against the Umbrella Facility. She was infected with the T-virus after touching a spot of dried blood on a gurney and then scratching her eye and subsquently turns into a zombie. Unlike other zombies that appear in the story, which carry some degree of cognative skills (they are able to take orders and fire weapons) and even poses the ability to speak, Karen becomes a regular zombie. She dies at Caliban Cove, She carries a old hand grenade for luck, this is used by Rebecca and David when they become trapped.