A Sierra Leone official says a corpse has tested positive for Ebola, the day after the World Health Organization declared the outbreak over in West Africa.
Francis Langoba Kelly, spokesman for the Office of National Security, told local radio Friday that tests on a woman who died in the country's north earlier this month were positive for the virus. Kelly said the country's level of preparedness is high and there is no cause for concern.
Nearly 4,000 people died before Sierra Leone was first declared free from transmission Nov. 7. Guinea marked that day on Nov. 29. Liberia had been declared Ebola-free twice before Thursday. Officials warned flare-ups were possible.
Ebola has killed more than 11,300 people, mostly in West Africa, since it emerged at the end of 2013.