The death toll from the Ebola outbreak has hit 932, as international health experts meet to discuss whether to declare the situation a crisis.

The death toll of the Ebola epidemic has neared 1000 as fears that the disease is now taking hold in Africa's most populous nation of Nigeria grow.

The spread of the disease comes as the World Health Organization (WHO) met in an emergency session in Geneva to decide whether to declare an international crisis.

The latest official toll across west Africa hit 932 deaths since the start of the year, it said on Wednesday, with 1711 confirmed cases, mostly in Guinea, Liberia and Sierra Leone.

The death of a nurse in Lagos, a megacity of more than 20 million people, came as 45 deaths were confirmed across west Africa between Saturday and Monday, with aid agencies, including Doctors Without Borders, saying the terrifying tropical disease is out of control.

In Liberia's capital Monrovia, where the dead have been left unburied on the streets or abandoned in their homes, President Ellen Johnson Sirleaf appealed for divine intervention and ordered three days of fasting and prayer.

And in Sierra Leone, which has the most confirmed infection cases, troops were sent to guard hospitals to "deter relatives and friends of Ebola patients from forcefully taking them from hospitals without medical consent", a presidential aide told AFP.

Returning Sierra Leonean troops serving with the African Union peacekeeping force in Somalia were ordered to remain in the war-torn country on Wednesday rather than risk returning home because of Ebola.

The closed-door WHO meeting was not expected to make a decision until Friday.

But the session itself underscored the severity of the threat posed by the disease, which causes severe fever and unstoppable bleeding.

Meanwhile, a Spanish air force plane left for Liberia on Wednesday to bring an infected Spanish missionary priest home for treatment.

Copyright AAP 2014.