Ebola outbreak could be controlled in three months.

David Nabarro told the BBC the number of Ebola cases was currently increasing exponentially, but greater community awareness would help contain the virus.

People were becoming aware that isolating those infected was the best way to prevent transmission, he added.

So far, there have been more than 8,300confirmed and suspected cases of Ebola, and at least 4,033 deaths.

'Quite frightening'

Most fatalities - 4,024 - have occurred in the west African countries of Guinea, Liberia and Sierra Leone. Cases have also been reported in Nigeria, Senegal, Spain and the US.

Mr Nabarro said that the number of new cases was "quite frightening", as the spread of the disease was currently accelerating.

At the beginning, many west African communities did not understand that the outbreak was an infectious disease, he said