Health officials feared an Ebola outbreak could be spreading in this Central African nation Thursday, as the mother of one of the 10 people killed so far developed symptoms of the deadly disease.

A blood sample was taken from the woman — the first person to show signs of the disease in Mekambo, a town of about 11,000 people near four afflicted villages, said provincial health director Dr. Prosper Abessolo-Mengue. Results were expected Friday.

Authorities were also waiting for the results of tests conducted on other people who came into contact with the victims in the northeastern province of Ogooue Ivindo, near the border with Republic of Congo, he said.

Experts from the World Health Organization planned to drive Friday to the remote, forested region to help contain the outbreak, WHO spokeswoman Ghislaine Moussouany said. Government health officials had earlier said the team left Thursday.

The five-member team — which includes experts from Europe and the United States — will help local authorities isolate and treat victims, as well as distribute protective equipment like gloves and masks to prevent contact with the bodily fluids of patients.

The highly contagious disease has killed 10 people and infected two others — including a woman who disappeared from her village late Tuesday or early Wednesday.

Health officials feared she had fled to relatives in Republic of Congo and could spread the disease. Authorities on the other side of the border were still looking for the woman Thursday.

Gabon's government first reported on Dec. 4 that it suspected an outbreak. WHO confirmed Sunday the disease was Ebola, which has similar symptoms to other, less deadly hemorrhagic fevers.

While a quarantine has not been imposed on the affected region, local authorities are monitoring movement to and from the area. Journalists have not been allowed to travel to the region.

This is the first documented outbreak of Ebola since last year, when 224 people — including health workers — died from the virus in Uganda.

Ebola is one of the most virulent viral diseases known to humankind, causing death in 50 to 90 percent of all clinically ill cases. But it usually kills its victims faster than it can spread, burning out before it can reach too far.

The virus is passed through contact with bodily fluids, such as mucus, saliva and blood, but is not airborne. It incubates for four to 10 days before flu-like symptoms set in. Eventually, the virus causes severe internal bleeding, vomiting and diarrhea.

There is no cure, but patients treated early for dehydration have a good chance of survival.

WHO says more than 800 people have died of the disease since the virus was first identified in 1976 in western Sudan and in a nearby region of Zaire, now Congo.