An epidemic of Ebola virus disease occurred in Liberia from 2014 to 2015, along with the neighbouring countries of Guinea and Sierra Leone. The first cases of virus were reported by late March 2014. The Ebola virus, a biosafety level four pathogen, is an RNA virus discovered in 1976. Before the outbreak of the Ebola epidemic the country had 50 doctors for its population of 4.3 million. The country's health system was seriously weakened by a civil war that ended in 2003.