Two potential vaccines against the deadly Ebola virus ravaging West Africa could be available as soon as November and would first be given to health care workers most at risk of exposure to the disease there, the World Health Organization announced on Friday.
The organization also announced that blood from recovered Ebola patients and serums derived from that blood should be used to treat the sick, and it said treatment centers should quickly begin testing other experimental therapies to combat the viral disease, which has escalated into a devastating health crisis.
“We have to change the sense there is no hope in this situation to a realistic hope,” Dr. Marie-Paule Kieny, an assistant director general, told a telephone news conference at the conclusion of a two-day meeting at the organization’s Geneva headquarters aimed at expediting the prevention and cure of Ebola. The disease has now killed nearly 2,100 people over the past six months. Nearly all the deaths have been in three West African countries — Guinea, Liberia and Sierra Leone — but clusters of Ebola patients have recently been found in Nigeria, Africa’s most populous country.
Dr. Kieny said nearly 200 scientists, ethicists and clinicians from around the world had reached a consensus in identifying the most promising vaccines and potential treatments and developing strategies for testing them. The two vaccines, which have not yet been studied in humans, are set to undergo initial tests of their safety and immune system effects beginning this month in a small number of volunteers in Britain, the United States and Mali, which borders Guinea, where the outbreak emerged.
If the initial safety tests were encouraging, the vaccines, still under evaluation, should immediately be offered in stages to health workers and other “front line staff” in West Africa, according to a prioritization plan set by a panel of ethicists convened earlier this summer by the W.H.O., Dr. Kieny said.
The pace of testing, and the bypassing of normal protocols to develop the vaccines, is “absolutely unprecedented,” Dr. Kieny said. She said that the vaccine testing protocol was approved in Mali within days and that there had been a “change of all the processes that we know, for this particular Ebola outbreak.”
While it was likely that patents had been filed and intellectual property rights applied to some of the vaccines and treatments, she said, “so far we’ve seen absolutely no problem and no barrier to the use of these.”
Dr. Kieny stressed the importance of carefully monitoring results to ensure that vaccines were not harmful and did not paradoxically make people more susceptible to the disease. “We must also be conscious about that — rollout must happen as quickly as possible but step by step.”
Upward of 10,000 doses of one vaccine, based on a modified chimpanzee cold virus, may be available by the end of the year, according to materials produced by the W.H.O. The vaccine is being tested by its developers, GlaxoSmithKline and the United States National Institutes of Health, and a British consortium. An initial 800 doses of the second vaccine were donated by the Canadian government to the W.H.O., Dr. Kieny said.
“I would love to be the first African” to receive one of the vaccines, Dr. Samba Sow, director general at the Center for Vaccine Development in Mali, told the news conference.
Participants at the conference also concluded that countries should be assisted in offering patients transfusions of whole blood, plasma, or so-called convalescent serum produced from the blood of people who have survived Ebola. “A blood-derived product can be used now, and this can be very effective in terms of treating patients,” Dr. Kieny said.
However, carrying out such efforts will require strong international support, given that Ebola treatment centers are short of staff and overwhelmed with far more patients than they can handle, leaving care at the most basic level.
Such blood transfusions were used with apparent success in several patients during the 1995 Ebola outbreak in Kikwit, Zaire, now the Democratic Republic of Congo. Oyewale Tomori, a professor of virology at Redeemer’s University in Nigeria, said at the news conference that blood was being collected for this purpose from five Ebola survivors in Nigeria. It was reported that Dr. Kent Brantly, a missionary doctor who contracted Ebola in Liberia and recovered, received a blood transfusion from a patient that he had treated before being evacuated to the United States.
A handful of other potential Ebola treatments selected for their promise, including the antibody mixture known as ZMapp, should be evaluated in treatment centers in West Africa as protocols are developed and doses become available, the W.H.O. said. Each patient would be informed of the risks and benefits, and the effects would be evaluated.
The meeting in Geneva was part of a broader mobilization within the United Nations system to counter the spread of Ebola. Secretary General Ban Ki-moon, speaking to reporters in New York, called the mobilization “an international rescue call.”
“The number of cases is rising exponentially,” he said. “The disease is spreading far faster than the response. People are increasingly frustrated that it is not being controlled.”
W.H.O. officials recently estimated it would cost $600 million to fight the Ebola scourge, the worst in the nearly 40-year history of the disease, and that 20,000 people could be infected before it is brought under control. “One of the things driving fear and panic in the communities and the world is the belief there is no treatment,” Dr. Kieny said.
A version of this article appears in print on September 6, 2014, on page A10 of the New York edition with the headline: Two Vaccines to Protect Against Ebola Could Be Available Within Weeks .
Source: http://www.nytimes.com/
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