Ebola crisis: Virus reaches the last untouched corner of Sierra Leone

The mountainous Koinadugu district had escaped the disease until Thursday

Health workers spray themselves with chlorine disinfectants after removing the body a woman who died of Ebola virus in the Aberdeen district of Freetown, Sierra Leone

The Ebola outbreak has reached the last untouched corner of Sierra Leone, infecting two people as the World Health Organisation (WHO) warned new cases “continue to explode”.

Almost 1,200 people have been killed in the country, which is one of the three countries in West Africa worst-hit by the disease.

Until Thursday, the north-eastern district of Koinadugu had escaped but two cases have now been recorded, raising the prospect of many more.

It is the largest of Sierra Leone’s 14 districts by area, with an estimated population of 260,000 people, and is on the border of Guinea, which is also being ravaged by Ebola.

Residents had practiced strict safety precautions and limited contact with the rest of the country where the disease is rampant.

Surrounded by mountains, guards with thermometers and disinfectant had staffed checkpoints restricting movement in and out.

It is unclear how the virus finally reached Koinadugu but Ebola is raging out of control in the rest of Sierra Leone, according to WHO, which recorded 425 new cases in the last week.

A dwelling is disinfected in Magbonkoh, Sierra Leone (Getty) (Getty Images)

“In Guinea, Liberia, and Sierra Leone, new cases continue to explode in areas that looked like they were coming under control,” a spokesperson said.

“WHO epidemiologists see no signs that the outbreaks in any of these three countries are coming under control.”

At least 4,500 people have died from Ebola there so far but the situation is more positive elsewhere.

The end of the outbreak is due to be officially declared in Senegal tomorrow and in Nigeria on Monday as both countries pass the 42-day mark since a case was recorded.

The British Government has pledged £125 million to support the global effort to control and defeat the disease in Sierra Leone.

British military personnel train for a deployment to Sierra Leone in support of the ebola outbreak in the country (Getty Images)

The latest aid flight landed in the capital, Freetown, on Sunday carrying beds, protection suits, tents and vehicles.

Five specialist treatment facilities are being built from scratch.

Discharging celebrations are being held for Ebola survivors at some medical centres in Sierra Leone.

On Tuesday, the Ministry of Health held a ceremony for 33 treated patients from the Hastings Ebola Treatment Centre, near Freetown.

The survivors included five children aged between two and four, a spokesperson said.

Officials and a nurse who overcame the disease, Fonti Kargbo, spoke at the ceremony, where certificates and free food, clothes and toiletries were given out.

As the fight continues to stop Ebola in West Africa, concerns about it spreading in the US are growing after two nurses contracted the virus while treating a patient who later died in Texas.

One of the women boarded a flight before she knew she was infected, sparking an operation to trace more than 130 of her fellow passengers.