"This is the first effort to have a long overdue, transparent, public discussion about how to distribute life-saving medicines in an emergency," said Arthur Caplan, a director of a medical ethics division at New York University. "A ton of attention is going to follow this panel."

US regulators last week said a treatment by Tekmira Pharmaceuticals could be tested in infected patients, while a drug by Mapp Biopharmaceutical has already been used to treat two Americans and a Spanish priest infected in Africa. While relatives and supporters have said the two Americans were improving, it remains unclear if the drug helped.

There is no cure for Ebola. The disease is normally treated by keeping patients hydrated, replacing lost blood and using antibiotics to fight off opportunistic infections. The hope is that a patient's immune system will eventually fight off the virus' aggressive attack.

If it was decided an experimental drug should be used, the next question would be "under what conditions should people get it", said Caplan, who will not be part of the WHO panel.

"Only people with informed consent? Do you think you'll ever get informed consent from the poorest person in Guinea? Does the government say yes for them?"

The limited supply also created problems, he said, questioning whether a patient's condition should matter.

"The more recently you've been infected, the more likely you'll respond better than if you're 20 days out," he said. "How about young versus old? Do we care if you're 10 or if you're 80?"

Ebola has killed 961 people and sickened 1,779 in West Africa since it was first reported, the WHO said August 8. It began in December with a two-year-old child in Guinea, according to research published in April in the . Since then, the disease has raced through Guinea, Liberia and Sierra Leone, and recently entered Nigeria.

Hopes for a treatment were raised when two American health workers, Kent Brantly and Nancy Writebol, reportedly improved after receiving an antibody cocktail dubbed ZMapp, made by San Diego biotechnology firm Mapp. Brantly and Writebol were flown to Atlanta, where they are being treated at Emory University Hospital.

Local and foreign aid workers like Brantly and Writebol, who chose to use the drug, should be first on the list to receive the new treatments, said Erica Saphire, a molecular biologist at the Scripps Research Institute.

"They are taking care of others at great risk to themselves," Saphire said.

"If the treatments help them survive, they could return to care for other patients, so the effect of the treatment would be compounded. Further, the health-care workers that survive may even become immune, and much better able to help in the future."

G.Kevin Donovan, director of the Pellegrino Centre for Clinical Bioethics at Georgetown University, argued that African doctors should be getting the same chance at potentially life-saving intervention.

"There is no reason why African doctors shouldn't be considered as eligible" to be flown to Western countries for treatment, Donovan said.

"The sad truth is they are working in their own countries, which are terribly underfunded and terribly understaffed. The reason it worked for these two Americans is their organisations had the will and resources to pluck them out of danger."

He said the inability of West African aid workers to get top-notch treatment was "a reflection of the inherent inequalities in the world and it doesn't make it right. It makes it sadder and even more admirable for these local doctors and nurses to be placing themselves in such a position".

Another question was whether the companies making drugs would let their treatments be used widely, Caplan said. The WHO could only make recommendations, and could not compel drugmakers to share their treatments, he said.

"They may be nervous if they have a drug that needs to be refrigerated transported, and may not be handled properly. If lots of people die, it'll be held against their drug," which could hurt the therapy's chances of eventually reaching market, Caplan said.

"They may be accused of experimenting on illiterate, poor people."

Besides Mapp's drug, Vancouver-based Tekmira is also developing a treatment, which is stalled in clinical trials due to safety concerns. Still, the US Food and Drug Administration said it could potentially be used in an emergency situation. The US National Institute of Health is also developing a vaccine, which may begin enrolment in a phase one clinical trial by this autumn.

Mapp was "cooperating with appropriate government agencies to increase production as quickly as possible" it said in a statement on its website. Tekmira spokeswoman Julie Rezler did not return a call asking about treatment availability.

The WHO, which is organising the ethics panel, has come under criticism from some aid groups for not being aggressive enough in fighting what it last week designated an international public-health emergency.

"There is a lack of coordination among all the different partners," said Koen Henckaerts, a health expert at the European Commission's humanitarian aid division, speaking from Monrovia in Liberia. "The WHO has a big responsibility to do more than just give technical advice."

Doctors Without Borders, with almost 700 workers in the affected region, was also critical, saying in a statement that it had been repeating for weeks that "a massive medical, epidemiological and public-health response is desperately needed to save lives and reverse the course of the epidemic".

Guinea has closed its border with Sierra Leone until the virus is under control. It also shut its border with Liberia, Reuters reported, citing Health Minister Remy Lamah. Health authorities in Nouadhibou, Mauritania's second-largest city, set checkpoints at port, airport and land routes, news site Mauriweb reported.

At the moment, stopping further spread of the outbreak was the top priority, as available quantities of experimental treatments were too low to make an impact, Caplan said.

''At this point, is it even worth arguing about it?" he asked, referring to the WHO's discussion on experimental treatment use.

"Even if they ramped up production of the Mapp drug tomorrow, they may be able to get 30 doses of the drug. It's not going to stop the outbreak."