London (AFP) - The Ebola virus will be contained in Sierra Leone by the end of the year, the president of the badly affected country told Britain's ITV News on Thursday.

"I am of the view that by the end of the year, we'll be in a position of not eliminating but containing the Ebola virus," President Ernest Bai Koroma said.

The World Health Organisation (WHO) has described the spreading outbreak, which has claimed 4,900 lives including at least 1,200 in Sierra Leone, as a global public health emergency.

He defended his government's handling of the crisis.

"The Ebola outbreak was announced in May and it was new to all of us. We are not alone in the fight," Koroma said.

"We also had the WHO who principally advised us on what to do and every step of the way we have had consultations with them and I believe we have been reacting appropriately."

Sierra Leone is one of the countries worst affected by the epidemic, along with its west African neighbours Guinea and Liberia.

The World Bank warned earlier this month that if the disease is not contained in the three countries by the end of the year, the economic cost to west Africa could rise to nearly $33 billion (26 billion euros) in 2015.

Health teams in Sierra Leone have been working desperately to contain the virus, which is normally fatal and has no vaccine or reliable cure.

Britain has sent military and medical staff to help the outbreak in Sierra Leone, and several countries worldwide have begun screening air passengers from the affected countries.