Western countries scrambled to put airport security measures in place on Friday amid mounting concern about the spread of Ebola world-wide.

New measures to screen travelers for the deadly virus were being considered as the United Nations made an urgent appeal for cash after receiving just $100,000 for a crisis fund to tackle the deadly epidemic.

Lawmakers in the United States grilled officials over how an infected nurse was allowed to board a crowded flight, and European officials promised a review of how passengers from Ebola-hit countries are screened.

UN Secretary-General Ban Ki-moon said the call for donations to a trust fund had fallen on deaf ears, leaving "a very serious problem", as experts warned that the death toll from the disease may be about to spiral.

Despite $20 million of pledges, there was only $100,000 in the reserve fund - reportedly donated by Colombia - he told reporters in New York.

With only a quarter of the UN's overall $1 billion Ebola target pledged, Ban praised the US, Britain and France, but said other countries need to do their share. "Now it is time for other countries that have capacity... to provide financial support and other logistical support.

"We need to turn pledges into action. We need more doctors, nurses, equipment, treatment centers and medical evacuation capacities."

His predecessor Kofi Annan was even more stinging in his criticism of the world's response, saying that wealthy countries were slow to tackle the crisis because it began in Africa.

"If the crisis had hit some other region it probably would have been handled very differently," the Ghanaian diplomat told the BBC.

"In fact, when you look at the evolution of the crisis, the international community really woke up when the disease got to America and Europe."

Ban said an increase in donations was crucial, with fears growing of a spread beyond Africa as the death toll nears 4,500.

"I appeal to the international community to provide the $1 billion that will enable us to get ahead of the curve and meet our target of reducing the rate of transmission by December 1," he said.

Senegal 'Ebola free'

Senegal is officially free of Ebola, with the benchmark of 42 days without the disease having passed without any new cases, the WHO said on Friday.

"WHO officially declares the Ebola outbreak in Senegal over and commends the country on its diligence to end the transmission of the virus," the UN health agency said in a statement.

But doctors in Spain have identified six more cases of possible infection, including a missionary priest who recently returned from Liberia and has shown signs of fever. Two tested negative for the disease, officials said on Friday.

In France, a nurse who had earlier helped treat a returning Ebola patient was taken to a military hospital with what an official called a "suspect fever".

(China Daily 10/18/2014 page12)