Sierra Leone chief Ebola doctor infected Published duration 23 July 2014

image copyright Reuters image caption Nurses at Kenema's hospital want MSF to take on the Ebola cases

The doctor leading the fight against Ebola in Sierra Leone is now being treated for the deadly virus, a statement from the presidency has said.

Sheik Umar Khan tested positive and has been admitted to hospital in Kailahun, the epicentre of the outbreak.

More than 630 people have died of Ebola in the three West African states since the outbreak began in Guinea in February, United Nations figures show.

It is the world's deadliest outbreak to date and there is no cure for Ebola.

media caption The current outbreak is the deadliest since Ebola was discovered in 1976

It kills up to 90% of those infected but if patients receive early treatment, they have a better chance of survival.

It spreads through contact with an infected person's bodily fluids.

'National hero'

The statement from State House said that the minister of health was in tears when she heard the news about Dr Khan.

WHO: Latest West Africa Ebola outbreak figures

Guinea - 310 deaths, 410 cases

- 310 deaths, 410 cases Liberia - 116 deaths, 196 cases

- 116 deaths, 196 cases Sierra Leone - 206 deaths, 442 cases

Health Minister Miatta Kargbo called him a "national hero" and said she would "do anything and everything in my power to ensure he survives", Reuters news agency reports.

The Ebola cases in Sierra Leone are centred in the country's eastern districts of Kailahun and Kenema.

The BBC's Umaru Fofana in the capital, Freetown, says dozens of nurses at the government hospital in Kenema town - which treats all Ebola cases in the district - went on strike on Monday following the death of three of their colleagues of suspected Ebola.

But they have since suspended their sit-down strike as the government looks into their demands, which include the relocation of the Ebola ward from the hospital and the takeover of its operations by the medical charity Medecins Sans Frontieres.

On Saturday, the World Health Organization said that of the 632 deadly Ebola cases, 206 people had died in Sierra Leone.

Ebola virus disease (EVD)

image copyright Science Photo Library

Symptoms include high fever, bleeding and central nervous system damage

Fatality rate can reach 90%

Incubation period is two to 21 days

There is no vaccine or cure

Supportive care such as rehydrating patients who have diarrhoea and vomiting can help recovery

Fruit bats are considered to be the natural host of the virus