An illness that has killed nearly 100 people in northern Angola was identified on Tuesday as Marburg virus, which is in the same family of hemorrhagic fever diseases as the Ebola virus, state and UN officials said.

Described as “very virulent” and “very contagious” and transmitted through bodily fluids, the hemorrhagic fever threatens to spread from the northern Uige province to other parts of the country.

“This is a possibility. The incubation period is 21 days so we must reinforce the surveillance in neighbouring provinces and especially in Luanda,” Vice Minister for Health Jose Van Dunem told Reuters.

Some 107 people in Uige have fallen victim to Marburg, for which there is no cure, with the number of deaths attributed to the epidemic now standing at 96.

Experts last week ruled out Ebola infection, but had not yet pinpointed the disease that struck in Uige, about 225 km (140 miles) north of Luanda.

With a health infrastructure shattered by a devastating civil war, Angola is facing monumental challenges trying to combat the virus.

“The mortality rate is around 30 percent in good hospitals. In hospitals like ours in Uige where the quality is not so high we have a higher (rate of) mortality,” Van Dunem said.

“We are trying to do our best by using our national capacity and asking for international support,” he added.

The World Health Organisation and Atlanta’s Centers for Disease Control and Prevention (CDC), which diagnosed the virus, have sent in experts, and medical nongovernmental organisations have also given their support, Van Dunem said.

Portugal has already warned its nationals not to travel to Uige but Van Dunem said the Angolan government would not issue similar warnings.

“The illness is contracted by secretions. If you don’t touch an infected person, you don’t risk being contaminated. So it doesn’t make sense to (stop) a person from going there,” he said.

The Marburg virus is characterised by high fever, headaches, nausea, with vomiting, diarrhoea and hemorrhaging. Most of the dead are children under five years old.