Ebola has long been the substance of nightmares, a chilling symbol of the fragility of our bodies in the face of nature’s power. Before the most recent outbreak began in the jungles of northern Guinea last March, most of what people in the West thought they knew of the disease came from Hollywood thrillers like Outbreak and Richard Preston’s sensationalist bestseller, The Hot Zone. Over the past year, rumors of liquefying organs and airborne transmission consumed the Western world, at times drowning out scientific debate and overshadowing the tragedy that was unfolding in West Africa.
Despite the hysterical media coverage that the ongoing Ebola outbreak has received, the epidemic has also dispelled many of the myths that people believed about the disease. The infected doctor Craig Spencer’s subway rides didn’t cause any other infections, demonstrating that the virus does not spread easily, and the deaths of Ebola patients in West Africa tended to be far less gruesome than what Preston and other writers had previously portrayed. Most surprisingly, the 80-percent survival rate among patients who were evacuated to Western hospitals shattered the idea that an Ebola diagnosis spelled near-certain death. I know this all too well, as I’m one of those patients myself.
In October, I contracted Ebola while covering the outbreak as a freelance journalist in Liberia. I was airlifted to a hospital in Nebraska, where aggressive treatment likely saved my life. Immediately upon my arrival, doctors inserted an intravenous line into my jugular vein to hydrate and nourish me. I was given an experimental drug, Brincidofovir, and a blood-plasma transfusion from Ebola survivor Kent Brantly. Two doctors examined me each morning, and a team of nurses watched over me around the clock, often rotating shifts to be directly next to me at all times. A team of nurses watched over me around the clock, often rotating shifts to be directly next to me at all times.
A little more than two weeks after I arrived in the U.S., a blood test confirmed that I was Ebola-free. In West Africa, however, my experience likely would have been far different, possibly with a much less fortunate outcome. Statistics released by theWorld Health Organization in early February show that more than 22,000 people in the region have been infected with Ebola so far, and close to 9,000 have died. This means that the death rate so far has been at least 40 percent, a figure that would likely be higher if all of the unreported cases were factored in. The Economist has reported that estimates of the mortality rate for this outbreak put it closer to 60 percent, indicating that the virus is two to three times as deadly for people in West Africa as it is for those of us lucky enough to be airlifted to a place with more advanced medical care.
Without an antiviral drug to target the virus itself, Ebola treatment is a race to keep the symptoms of the disease at bay until the body can manufacture enough antibodies to fight off the infection. But while a modern hospital is clearly a better place to weather Ebola than a field treatment unit, health workers are still unclear about the best way to bring up survival rates in the latter. No one seems to know which treatment, out of the many I received, is the one that saved my life.
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From the moment I was diagnosed in Liberia, dehydration was a constant fear. The vomiting and diarrhea associated with Ebola can quickly become life-threatening as the body shuts down essential functions in the kidneys and other vital organs. This has led some people to compare it to cholera, another tropical disease that kills via fluid loss—and whose survival rates can be as high as 99 percent, if the patient is treated with aggressive IV rehydration. Some havesuggested that the similar treatment for Ebola patients in Western facilities is why so many of us have lived.
But the value of IV rehydration has been a point of contention among health workers in the field, particularly after Doctors Without Borders temporarily suspended the use of IVs in its Monrovia facility last September. According to Armand Sprecher, a physician and public-health specialist with DWB, the decision was based on the difficulties of treating such a high volume of patients. In September, the height of the outbreak in Liberia, people were often turned away from health facilities because of lack of space. Part of the challenge in administering IV fluids under such crowded conditions was the near-impossibility of attending to each patient for more than a few moments at a time: IV fluid replacement requires sustained attention, as giving a patient too much or too little can prove deadly. DWB also expressed concern for its staff members, who, with their overwhelming workloads, ran a greater risk of infecting themselves with accidental needle pricks while inserting or removing IVs.
But while Sprecher acknowledges the importance of IV rehydration—DWB reinstated the practice in October—he’s also skeptical that rehydration alone can explain the high survival rates of Western patients. Death rates in the Monrovia facility, he notes, were similar during and after the September IV suspension. “That’s not a reason to say it doesn’t work. It’s just reason to dampen down the optimism of people who think that this judicious application of IV therapy is what pulls people back from the grave,” he says, adding that he believes sepsis, or blood poisoning, is a more common cause of death than dehydration.
Still, aggressive IV fluid replacement was a cornerstone of the treatment given to Ebola patients who were evacuated to the West, myself included. “We think that getting a good, secure IV line into patients, and giving cautious but aggressive fluids, is the best thing we did,” says Phil Smith, the physician at the Nebraska Medical Center who treated me and two other Ebola patients last year. Atai Omoruto, a Ugandan doctor who ran one of the World Health Organization’s treatment facilities in Monrovia until December, agrees, saying that the insertion of an IV line was one of her first concerns when admitting new arrivals. Nonetheless, she says the death rate at her facility was around 40 percent.
Besides dehydration, fluid loss poses another danger for Ebola patients: electrolyte deficiencies, which can lead to heart attacks and other complications. “If one can know the electrolyte situation, the patient’s chances of survival are increased,” Omoruto says, but “we lost several of our patients from cardiac arrest due to low potassium.” In Nebraska, doctors analyzed my blood for its mineral content on a regular basis—but in West Africa, the equipment needed to perform those tests is rarely available, and experimental mobile technology has proved unreliable, Sprecher says.
Blood transfusions like the one I received from Kent Brantly, by contrast, are a straightforward procedure that health workers in the field can do with relative ease. But still, they’re rarely administered in West Africa, because doctors still aren’t 100 percent sure that they work.
When the outbreak began, there was some debate between the WHO and DWB about the value of these transfusions, which involve the donation of blood plasma from Ebola survivors. The thinking behind the treatment is that antibodies in the survivors’ plasma already know how to fight the virus, and therefore might help to decrease a new patient’s viral load and kickstart his or her immune system. I felt markedly better the day after receivingmy transfusion, although my doctors said there’s no way to know for certain if it was a result of the procedure or simply a coincidence in the timing of my recovery.
Shevin Jacob, an infectious-disease specialist who has worked with the WHO in Sierra Leone and Liberia, says plasma transfusions are still considered an “investigational therapeutic.” There is some evidence that they work—in one well-known study from the mid-1990s, seven out of eight Ebola patients survived after receiving survivors’ blood—but there’s still not enough data to convince the WHO and other health organizations, many of which are hesitant to incorporate the procedure into existing treatment guidelines. “For us to say [that] everyone should be getting this therapy when we don’t know if it’s truly beneficial is almost unethical,” Jacob says. On the other side of the issue, Omoruto recalls being frustrated that she was not permitted to give transfusions from survivors to her patients, and remembers clashing with DWB over their potential treatment value.
To get definitive answers about the effectiveness of blood transfusions or experimental drugs, health officials say they would need to conduct studies with patients who are suffering from Ebola—a grim prospect, and one that would almost certainly go over poorly in West Africa, where many people are already suspicious of Western health workers. But Jacob, the WHO infectious-disease specialist, says the benefits of such studies could be enormous: “In the middle of an outbreak, doing a study seems almost crass, but if it helps you get answers you could maybe save more people,” he says. “The possibility of the outbreak ending and us not having a ton more information because of the barriers is real, and we might regret that eventually.”
My case, and the cases of the other Ebola patients treated outside of West Africa, probably won’t shed much light on the effectiveness of any one treatment. As Smith, the Nebraska physician, puts it, “We decided that because the disease was associated with such a high mortality rate, we wanted to give every safe intervention that we could.” This “kitchen sink” approach that I and other patients in the West received may have kept us alive, but it’s also made it difficult for doctors to determine which element was most responsible for our recovery. Compounding the confusion, factors beyond medical care almost certainly played a role in our survival as well. When I contracted Ebola, I, like most other Western patients, was young, well-fed, and in relatively good physical shape.
And even among patients in West Africa, there is no obvious answer as to why some die and others live. Age is one predictive factor: According to the WHO, patients under 40 are 3.5 times more likely to survive than their older counterparts. Healthcare workers also cite the initial viral load that patients were exposed to, their genetics, and even their emotional state as things that may influence survival. Omoruto says that some of the 1,300 patients she treated in Monrovia fell into despair after losing loved ones, which took its own physical toll. “For patients that were depressed, the survival rate was much lower,” she says.
While the current epidemic may be slowing in West Africa, it would be unwise to assume that another one will never come along—and Tom Frieden, director of the Centers for Disease Control and Prevention, has expressed fears that the virus could become endemic in the region. Last month, a collection of medical organizations, including DWB and the WHO, met in Geneva to discuss what an ideal Ebola-care program might look like.
But some, including DWB’s Sprecher, believe that without a drug that directly targets the Ebola virus, it’s unlikely that any treatment for its symptoms will be able to raise survival rates in West Africa much past where they are right now. “I’m not going to say it can’t be done, but it’s optimistic. The case fatality ratio of our staff who were infected was around 50 percent,” he says. “I know people are pulling out all the stops in treating these people. If it were just a matter of trying harder, you’d see it in their colleagues’ survival rates.”
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