As Sheik Umar Kahn, Samuel Brisbane, and Patrick Sawyer lay dying of Ebola virus disease this week, the West African hospitals where the men were being treated had few medical tools with which to try to save them. As is too often the case, the meager options failed.
The three—Sierra Leone's top Ebola doctor, the chief physician at Liberia's leading medical center, and a Liberian government official—are among at least 729 people who have died of Ebola in the current months-long outbreak. The first in West Africa and the largest on record, this Ebola epidemic has infected at least 1,323 people in Guinea, Sierra Leone, and Liberia.
Nigerian authorities are on tenterhooks waiting to see if Sawyer, who flew from Liberia to Lagos while sick, touched off any infections in Africa's most populous country. If the world is lucky, he did not. Still, it is inevitable that before the outbreak is snuffed out, many more people will contract the virus and many will die. (See "Q&A: Ebola Spreads in Africa—and Likely Will Spread Beyond.")
Researchers have been working for years on drugs that in theory could slow, or even halt, the current outbreak. But while promising, these therapeutics are stuck in developmental limbo. Consequently, there is currently no licensed vaccine to prevent Ebola nor licensed drugs to arrest infection.
Sufferers in West Africa who seek medical help are treated the way hospitals always care for Ebola patients. They receive broad-spectrum antibiotics to fend off opportunistic infections like pneumonia or sepsis that can slip in and kill when an immune system is overwhelmed.
They will be fed, if they can eat. And they will be given rehydration fluids to replace those that drain from bodies racked by diarrhea and vomiting. (These are more common symptoms of Ebola disease than the bleeding that is thought to be its hallmark; profuse bleeding is seen only in a small percentage of cases.)
Support, But No Cure
This is called supportive care, and the name says it all. For the most fortunate people, typically the ones who seek help early, supportive care can buy enough time to tip the balance in favor of the immune system, which is initially overpowered by Ebola's onslaught. For the unfortunate and the late, supportive care is a way to ease Ebola's nasty death.
The fact that there is no cure sets up an ugly dynamic between the people who catch the disease and the teams of volunteer medical professionals who try to contain Ebola outbreaks. (See "Why Deadly Ebola Virus Is Likely to Hit the U.S. But Not Spread.")
People who fear they may be infected are often reluctant to be tested; the disease carries huge stigma and is seen as a death sentence. Those who test positive may refuse to go to isolation centers for care, knowing full well the trip home may be in a sealed body bag.
The inability to visit the sick or conduct traditional burial rites for the dead—measures put in place to protect the uninfected—gives rise to fast-spreading rumors that have plagued containment efforts. (See "Ebola's Deadly Spread in Africa Driven by Public Health Failures, Cultural Beliefs.")
Rumors that foreign medical teams are infecting Africans or are killing them for their organs are not easy to combat when survival rates are so poor. Aid workers trying to identify and isolate cases are often met with rocks, sticks, or threats of violence.
But staying with their families does not save the infected and draws many of their caregivers into Ebola's deadly embrace. Cleaning up a sick person's vomit or diarrhea, or preparing a corpse for burial, spreads the virus from the sick and the dead to their family and friends.
If there were drugs to cure the disease, the long, village-emptying chains of Ebola transmission could be made a thing of the past.
"It would be a game changer," says Marc Forget, a Canadian doctor who experienced the hostility during a recent seven-week mission in Guinea with Médecins Sans Frontières (Doctors Without Borders). "You would be able to tell people: 'You have Ebola and I have a special drug that will kick out that virus. And the only way to get it is to come to the [treatment] center.'''
Promising Therapies, Vaccines
Yet, some experimental therapies and vaccines show promise. Some show excellent efficacy when given to nonhuman primates deliberately infected with the virus.
Of the experimental vaccines, most work only to protect against infection. But one—designed by scientists from the Public Health Agency of Canada in conjunction with the U.S. Army Medical Research Institute of Infectious Diseases at Fort Detrick, Maryland—protected half of the animals injected with lethal amounts of Ebola virus when administered 30 minutes post exposure.
It was given to a German researcher who pricked herself with a needle while working with Ebola virus in 2009. The woman survived, but it is not known if the vaccine saved her. She might not have been infected.
A number of drugs are also in development. Various research groups are working on combinations of monoclonal antibodies—antibodies that target the protein on the outside of the Ebola virus that have been isolated and cloned. These appear to be highly effective in animal testing.
Another option, a compound called an RNA interference drug, is in phase I clinical trials in healthy humans, though the Food and Drug Administration has placed a hold on the work as it seeks more information about a reaction experienced by one of the subjects.
Despite promising results, these countermeasures have languished in laboratories. Developing a drug or a vaccine is enormously expensive, and there is no chance a pharmaceutical company could recoup its costs selling an Ebola therapy.
Though outbreaks are high profile, they are rare. Fewer than 4,000 people are known to have been infected since Ebola was first identified in 1976. Vaccinating broadly in Africa would not make economic sense even if the affected countries could afford a vaccine.
As a result, the major players have ceded this field to small biotech firms and laboratories funded by governments.
"There's really not much profit in it for them. Not like cancer drugs or like heart disease medication or even an infectious disease that's more prevalent like malaria or something," says Tom Geisbert, a microbiology and immunology professor at the University of Texas Medical Branch at Galveston who has helped develop several of these interventions.
Without Big Pharma's deep pockets, those involved in the work have struggled to figure out how to push these tools through the regulatory pipeline.
Virologist Heinz Feldmann, who led the research on one of the vaccines, notes that when he tried to find a company to make human-use—quality supplies of the vaccine-a prerequisite for conducting human studies—he was told one batch would cost between $2 million and $4 million.
He and others have been frustrated by the impasse. The only way to prove to regulatory agencies that these products work in humans is by using them in people who have Ebola or have been exposed to Ebola. But short of a lab accident—dreaded in this community—that can be done only during an outbreak in Africa.
The idea of using in Africa drugs or vaccines bolstered only by animal studies and small safety trials in healthy humans makes many in the research community nervous. Says Geisbert: "None of us, certainly, want to have something that we develop cause problems in humans. So it's just a difficult situation."
And the idea of trying to embed a clinical trial within the current outbreak response strikes many as an impossibility, given the gargantuan task the responders face and the level of mistrust between them and affected communities.
At various points in this outbreak there have been calls to use the experimental therapies.
Feldmann, an Ebola expert who heads the virology laboratory at the National Institute of Allergy and Infectious Diseases' Rocky Mountain Laboratories in Hamilton, Montana, was approached by Médecins Sans Frontières at the start of the outbreak. The group wanted advice on whether it could protect the teams it would be sending into the field. But nothing came of the discussion.
Feldmann says lately there has been renewed talk about using the available products to protect response teams, a debate reignited by the infections of responders like Kahn and Brisbane, as well as Americans Kent Brantly, a doctor, and Nancy Writebol, a missionary involved in the containment effort. But the idea of protecting some and not others is ethically troubling.
And it is unclear how much human-grade product actually exists; there could be very little. Whether the governments or companies that own the supplies—and the patents on them—would be willing to release experimental drugs or vaccines is not clear either.
The upshot is that while in West Africa there is fear, in Ebola laboratories there is frustration. Feldmann notes his lab has been working for years on these products, and the researchers wonder if their work will ever make a difference in an outbreak. "People come to me from my own group and say, 'Does it mean anything, my work? Or is it just academic?'"
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