The World Health Organisation on Friday declared the killer Ebola epidemic ravaging parts of west Africa an international health emergency and appealed for global aid to help afflicted countries.

According to AFP, the decision came after a rare, two-day closed-door session of the UN health body's emergency committee, which urged exit screening of all people flying out of affected countries, where nearly 1,000 people have died.

The WHO stopped short of calling for global travel restrictions, urging airlines to take strict precautions but to continue flying to the area.

And it called on countries and airports around the globe to be prepared to "detect, investigate and manage" Ebola cases if they should arise.

The WHO move comes as US health authorities admitted on Thursday that Ebola's spread beyond west Africa was "inevitable", and after medical charity Doctors Without Borders (MSF) warned that the deadly virus was now "out of control" with more than 60 outbreak hotspots.