FREETOWN, Sierra Leone — A woman who died this week in Sierra Leone tested positive for Ebola, officials said Friday, a setback for the region that came only a day after the World Health Organization had declared the epidemic over.
WHO had warned Thursday that new Ebola cases were possible even after virus transmission was halted in Liberia, Sierra Leone and Guinea — the three West African nations hardest hit by the epidemic that left more than 11,300 people dead.
Already 10 other flareups have taken place in areas where virus transmission was thought to have ended, raising new questions about WHO procedures in assessing whether an epidemic was really over.
The global health body said Friday that Sierra Leone's government was moving rapidly to contain the new threat, but it was not immediately clear how the 22-year-old woman who died may have contracted Ebola — all known transmission chains in that country had been halted back in November.
Francis Langoba Kellie, a spokesman for Sierra Leone's Office of National Security, said on the radio that the woman had come from the country's Northern Kambia District and had gone to the Northern Tonkolili District for medical care.
Authorities are tracing her contacts and have dispatched teams to the area to investigate how she might have contracted the deadly virus and if she might have infected others. Certain areas will be quarantined.
WHO declared the latest Ebola outbreak over in Liberia on Thursday after no new cases emerged there during a 42-day waiting period. That benchmark had already been met in both Guinea and Sierra Leone.