Whole blood transfusions have already been used to treat some patients in West Africa, Marie-Paule Kieny, the WHO’s assistant director-general for health systems and innovation, said yesterday. The United Nations agency is helping governments in the affected countries to establish a system that can be reliably used to draw blood from survivors, prepare it and re- inject it safely into patients, she said.

The agency assessed a dozen drugs and vaccines in a two-day meeting, after a WHO ethics panel decided last month that unproven treatments could be used. While some of the experimental vaccines may finish safety trials within months, the blood of survivors, containing natural antibodies against the disease, is readily available in an outbreak in which 47 percent of more than 3,900 people infected have survived.

“This has a good chance to work, and this is something that can be produced now from the affected countries,” Kieny said yesterday at a briefing in Geneva.

Guinea, Nigeria

The outbreak has now killed 2,097 people among 3,944 reported cases in Liberia, Sierra Leone and Guinea, the WHO said yesterday. Nigeria has reported eight deaths from 23 cases, and Senegal has one case.

Sierra Leone received 18 new ambulances from the United Arab Emirates, Sidie Yayha Tunis, spokesman for Ministry of Health and Sanitation, said by phone. The African nation is expecting more cases of Ebola. The ambulances will help during a four-day curfew scheduled to start Sept. 18, when citizens won’t be allowed to leave their homes.

Survivor blood has been used before to treat Ebola. In 1995, during an outbreak in Kikwit in the Democratic Republic of Congo, seven of eight infected people given the therapy survived during an outbreak with an 80 percent fatality rate.

Subsequent studies in monkeys have shown conflicting results, and Kieny said she didn’t know how many people in the current outbreak have been treated with a blood serum or what the results of those treatments may be. It’s a strategy worth trying while testing continues on other therapies.

“This is something which is real-time, now,” she said.

Potential Donors

While the virus had killed 2,105 people as of yesterday, more than in all previous Ebola outbreaks combined, there are plenty of potential blood donors because almost half of those infected have survived, according to Kieny. “These people can provide blood, can provide serum, in order to have something to treat the other people who are sick.”

Once the blood is collected, doctors can test it for diseases including HIV and hepatitis, and separate out the plasma. Antibodies in plasma are produced by white blood cells in response to foreign invaders in the body. They bind to the microbes, either neutralizing them or flagging them for other parts of the immune system to attack.

The first results from safety trials of experimental vaccines may be available by November, according to Kieny. The shots could be used in health workers immediately if the data are positive, she said.

Vaccine Trials

NewLink Genetics Corp. said this week it received permission from the U.S. Food and Drug Administration to begin the first trials of its experimental Ebola vaccine in humans. About 40 healthy adults will be given the shot to determine the safety of the vaccine initially developed by the Public Health Agency of Canada. The Canadian government has donated 800 doses of the vaccine, she said.

The U.S. National Institutes of Health also began this week an early-stage trial on a vaccine it developed with London-based GlaxoSmithKline Plc. About 10,000 doses of that shot may be available by the end of the year, Kieny said.

Mapp Biopharmaceutical Inc.’s ZMapp, given to two U.S. aid workers who survived the disease after being transported from Liberia and treated in Atlanta, has shown “encouraging signs,” she said. However, there’s not enough evidence demonstrating conclusively whether it works, and the supply of the drug is exhausted, Kieny said. The experimental medicine will be used as more supplies become available, she said.