Treatment for deadly Ebola virus advances

By Emma Ross
The Associated Press

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Experts said the results represent the biggest advance yet in the quest for a drug against Ebola Hemorrhagic Fever, one of the most feared diseases. World Health Organization doctors said they plan to try the drug on humans during the next outbreak.

"You take the patients from their families, they die in the ward, you bury them. Everybody is dying, and you cannot do anything," said WHO Ebola expert Pierre Formenty, speaking from the front line of the latest outbreak in Congo. "If you can save one or two, it will be nice to come back and try to save lives and not just control outbreaks by burying people."

In the study, outlined this week in The Lancet medical journal, scientists at the U.S. Army Medical Research Institute of Infectious Diseases used a protein that blocks blood coagulation, considered to be a major problem in the disease.

Although it is called Ebola Hemorrhagic Fever, bleeding occurs in only about 40 percent of cases and often is not the cause of death. The affliction is so named because when there is hemorrhage, it is dramatic. The disease most often involves a shock syndrome in which multiple organs shut down at once.

The death rate varies from about 50 percent for milder strains of the virus to about 90 percent for the Zaire strain, which is ravaging the community in Mbomo, deep in the bush of Congo. Since the outbreak began in October, 31 people have been infected and 29 have died.

Scientists believe the virus cranks up the body's production of a substance called tissue factor, which is involved in making blood clots. The body's ability to regulate the thickness of the blood goes awry, clots start to congest the blood vessels and blood backs up, said the study's leader, Army virologist Thomas Geisbert.

Many strategies have cured mice and other rodents of Ebola but didn't work when tried in monkeys.

In this study, researchers injected 12 monkeys with a high dose of the Zaire strain of the Ebola virus, which is 100 percent fatal in monkeys.

Then, starting either 10 minutes after the lethal injection or 24 hours later, the scientists gave nine of the monkeys daily shots of the anticoagulation protein for 14 days. The other three monkeys received fake injections.

Tests showed clotting activity was dampened in the monkeys that received the treatment.

Three of the nine monkeys treated, or 33 percent, lived. All the monkeys who received the fake treatment died.

"We saved the lives of three out of nine monkeys," Geisbert said. "They are still eating biscuits in my lab. The virus is gone. They are healthy. They are cured."

Almost as impressive was the finding that those monkeys that were treated but died anyway survived for an average of 12 days — about four days longer than monkeys who had not received the treatment.

Experts said that delay in death could be crucial.

"What we're doing with Ebola is we're buying time. The difference between Ebola and AIDS is that with Ebola, you do have the possibility of an immune response and to get well — if you can hang around long enough," said C.J. Peters, director for biodefense at the Center for Biodefense and Emerging Infectious Diseases at University of Texas Medical Branch in Galveston, Texas.

Peters said the monkey results are encouraging for humans because they provide a stringent test. If anything, he said, death rates from Ebola are higher in monkeys than in humans.

In another advance in the battle against Ebola, WHO scientists reported success with a new diagnostic test they used for the first time in the Mbomo outbreak.

Formenty said a simple dipstick that turns blue in the presence of Ebola seems as accurate as genetic tests that are not practical for rural areas of Africa, where most Ebola outbreaks occur.

Emergency workers try to determine who has Ebola by observing patients' symptoms and asking about their contacts.

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