Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January if they are deemed safe, a top World Health Organization (WHO) official said Tuesday.
Speaking at a press conference in Geneva, Marie Paule Kieny, an assistant director general for the WHO, said clinical trials — currently either under way or planned in Europe, Africa and the United States — are expected to produce preliminary safety data on two vaccines by December.
If the vaccines are declared safe, Kieny said they would be used in trials in West Africa beginning in January to test their effectiveness among tens of thousands — but not millions — of people.
"I'm not suggesting at this moment that there would be mass vaccination campaigns at population levels starting in 2015," she said, adding that none of the volunteers who take part in the trials could accidentally contract Ebola from the testing.
Public health experts say that while such a development would be welcome, it does not solve the problem on its own.
Dr. Amesh Adalja, of the Infectious Diseases Society of America, said that a vaccine would play an important supplemental role, but that it “should not be seen as a panacea for this outbreak."
"Even when we do have this experimental vaccine in place, there’s still going to be the same public health interventions that are really going to turn the tide," Adalja said.
The Ebola outbreak in West Africa has already killed more than 4,500 people, mostly in Liberia, Guinea and Sierra Leone, since it emerged 10 months ago. Experts have said the world could face 10,000 new cases a week in two months if authorities do not take stronger steps to fight the deadly virus.
Sierra Leone’s government said Tuesday that the number of infected people in the country's western region is soaring, with more than 20 Ebola deaths reported each day. That region is on the opposite side of the country from where the first Ebola cases emerged.
One of the two vaccines that Kieny mentioned was co-developed by the U.S. National Institutes of Health and GlaxoSmithKline from a modified chimpanzee cold virus and an Ebola protein. It is in clinical trials now in the United Kingdom and in Mali, and will be used in trials in Lausanne, Switzerland, by the start of February.
The second front-runner, developed by the Public Health Agency of Canada and known as VSV-EBOV, has been sent to the U.S. Walter Reed Army Institute of Research in Maryland for testing on healthy volunteers, with preliminary results about its safety expected by December. The next stage would be to test it more broadly, including among those directly handling Ebola cases in West Africa.
The safety tests will be particularly important in identifying any potentially significant side effects of the vaccine.
“Vaccines that have been tried in non-human primates and have done very well, but sometimes when you give it to large amounts of humans, a safety signal [adverse effects that can be traced to the drug] may emerge and I think that’s important to look for," Adalja said.
Canada has donated 800 vials of VSV-EBOV to WHO, but the shipment was delayed by a Lufthansa pilots' strike. The vaccine is now expected to arrive in Switzerland on Wednesday for testing coordinated by the U.N. health agency among volunteers at the University Hospital of Geneva, and volunteers in Hamburg, Germany, and in Gabon and Kenya, Kieny said.
"These data are absolutely crucial to allow decision-making on what dose level should go in the efficacy testing in Africa," Kieny said. "We expect, we hope, to have a go-ahead by the end of the month."
That would allow the vaccine to be shipped for use in Africa immediately afterward.
Kieny said decisions regarding the vaccines — about "which strategy to use and how and where and who" — will be made in the next few weeks. Then vaccines will be given to health workers and select segments of the general population "early in 2015, in January," Kieny said.
At a separate news conference, WHO spokeswoman Fadela Chaib promised a thorough public audit of the agency's early missteps — and those by countries and partner organizations — in responding to the Ebola crisis.
"There is certainly a wish and a will to have this review," she said. "We know many elements need to be explained in the future ... [The] WHO will do that, but in the future; now our focus is on the response."
Al Jazeera and The Associated Press. Philip J. Victor contributed to this report.