The Ebola virus has been identified as the cause of an outbreak of hemorraghic fever believed to have killed nearly 60 people in southern Guinea, government officials say.
Dozens of cases have been recorded since the outbreak began early last month.
There is no known cure or vaccine for the highly contagious Ebola virus.
It is spread by close personal contact with people who are infected and kills between 25% and 90% of victims.
Outbreaks of Ebola occur primarily in remote villages in Central and West Africa, near tropical rainforests, the World Health Organization says.
“We got the first results from Lyon yesterday (Friday) which informed us of the presence of the Ebola virus as the cause of this outbreak,” Sakoba Keita, chief disease prevention officer at the Guinean health ministry, told AFP.
“The Ebola fever epidemic raging in southern Guinea since 9 February has left at least 59 dead out of 80 cases identified by our services on the ground,” he said.
“We are overwhelmed in the field, we are fighting against this epidemic with all the means we have at our disposal with the help of our partners but it is difficult.”
Medical aid charity Medecins sans Frontieres said on Saturday it would strengthen its team in Guinea and fly some 33 tonnes of drugs and isolation equipment in from Belgium and France.