Since the last week of September, cases have been reported from 17 districts in four of the Darfur states, but most of them are from Central Darfur state, the report said.

A week ago the health ministry said 84 suspected cases had been reported from two states during October and 32 of the patients had died.

Officials are awaiting results from a laboratory in Senegal to reconfirm the diagnosis as a first step towards beginning a vaccination programme possibly by early December.

There is no specific treatment for the viral illness found in tropical regions of Africa but it can be contained through the use of bed nets, insect repellents and long clothing.

"Vaccination is the single most important measure for preventing yellow fever," the WHO said.

A 2005 outbreak of the disease in Sudan's South Kordofan state caused 163 deaths out of 604 cases over about five months.

In January 2011, 35 people died of yellow fever in the Ivory Coast, the WHO said.

Ethnic minority rebels in Darfur rose up against the Arab-dominated Khartoum government in 2003. The United Nations estimates at least 300,000 people have died in the bloodshed but the government puts the death toll at 10,000.

Violence has now eased but overlapping conflicts persist—rebel-government clashes, inter-Arab and tribal fighting, as well as carjackings and other banditry.