The World Health Organization says suspected Ebola deaths in the Democratic Republic of Congo have doubled in just over a week.

The WHO says the figure has risen from 14 to 31 since September 5. All of the cases are in Orientale Province in northeastern Congo.

WHO spokesman Tarik Jasarevic says the outbreak zones remain in the Haut-Uélé territory, in the towns of Isiro and Viadana.

In an interview with VOA on Thursday, Jasarevic described the outbreak as “very active.” However, he noted, most of the latest deaths involved people who were previously infected.

“We are seeing more cases. There are also some new cases. But most of these cases of these additional deaths are no new alert cases but are those that have been traced and that have happened before.”

Five of the latest deaths involve health workers.

The World Health Organization is working with Congolese health workers to find active Ebola cases and trace people who may have had contact with an infected person.

The coordinated effort to contain the outbreak involves educating people about how the highly-contagious virus is spread.

The disease is spread through direct contact with the blood, saliva, sweat or other bodily fluids of sick individuals. Handling the corpses of those who have died from the disease can also spread infection.

Humans can contract the virus if they eat infected forest animals, such as monkeys and antelope which are often killed for meat.

Jasarevic said the virus can incubate for up to 21 days and the death rate can be as high as 90 percent.

Symptoms include a sudden onset of fever, extreme weakness and muscle aches. Vomiting and diarrhea may occur. In rare cases of so-called Ebola hemorrhagic fever, patients suffer from internal and external bleeding.

Currently, there is no cure for Ebola, nor are there any specific treatments.