Hypothermia is the cause of at least 1,500 deaths a year in the United States. It is more common in older people and males. One of the lowest documented body temperatures from which someone with accidental hypothermia has survived is in a near-drowning of a 7-year-old girl in Sweden. Survival after more than six hours of CPR has been described. In individuals for whom ECMO or bypass is used, survival is around 50%. Deaths due to hypothermia have played an important role in many wars. The term is from Greek ὑπο, "hupo", meaning "under", and θερμία, "thermía", meaning "heat". The opposite of hypothermia is hyperthermia, an increased body temperature due to failed thermoregulation.