- As many as 55 people quarantined in Mali after girl's death
- Latest WHO figures put total death toll at 4,922 as of Thursday
- There is currently no cure or vaccine for Ebola
- Scores of international companies are working on experimental vaccines
As the world reels from its deadliest Ebola outbreak, health experts are fast-tracking tests for various vaccines, and hope to have millions of experimental doses by next year.
There is currently no cure or vaccine for Ebola, which continues to spread in Liberia, Sierra Leone and Guinea.
The virus has killed nearly 5,000 people -- mostly in those three nations -- and infected twice that number.
Scientists racing to stop the epidemic are trying various experimental drugs on patients, including ZMapp and TKM-Ebola.
In addition to drug development, there's a scramble to develop vaccines, with scores of companies working on experimental doses, the World Health Organization said this week.
Health care workers in affected nations will get the first opportunity to try the experimental vaccines.
GlaxoSmithKline and the Public Health Agency of Canada are already conducting the first phase of clinical trials for two experimental vaccines, according to the WHO.
The latter hopes to have 12 million experimental doses by the first quarter of next year.
The GSK vaccine is being tried on healthy volunteers in the United Kingdom and Mali; the Canadian one is undergoing testing on healthy volunteers in the United States.
"If the vaccines are determined to be safe, tens of thousands of doses could be used in West African trials beginning in January of next year," the WHO said.
Other vaccines in the works include those by Protein Sciences and Inovio, and another one by Russian scientists.
According to the latest WHO figures released Saturday, there have been at least 10,141 cases of Ebola -- with 4,922 reported deaths -- as of Thursday.
Liberia, Sierra Leone and Guinea account for nearly all the cases.
All but one district in Liberia and all districts in Sierra Leone have reported at least one case of Ebola since the start of the outbreak in March, the WHO said.
About 450 health workers have caught the virus worldwide. Of those, 244 have died.
Ebola is spread by direct contact with the bodily fluids of an infected person. The push for vaccines came as new cases of Ebola were confirmed in New York and Mali, the latter the first case in that nation.