Medical experts have warned of a risk of a resurgence of the Ebola virus in West Africa.
Speakers at a health conference in Senegal, warned that without increased vigilance, the disease could reappear at any time in Sierra Leone, Guinea and Liberia.
The three countries were the most affected by the epidemic.
More than 28,000 cases were recorded with more than 11,000 people dying during the most complicated ebola epidemic which hit West Africa.
The World Health Organization declared in March that Ebola was no longer an international public health emergency.
But Sierra Leone, Guinea and Liberia experienced new cases of Ebola, starting the clock over again.