Jul 23, 2012

Undead: The Rabies Virus Remains a Medical Mystery

Eight years old, wiry and ponytailed, Precious Reynolds bounds from the elevator to the entrance of the pediatric intensive-care unit. She fidgets impatiently as she waits to be buzzed in, eager to return to the clinic where, by the ironclad expectations of 2,000 years of medicine, she should have died. It was nine months ago, here at the UC Davis Medical Center in Sacramento, California, that Precious survived a confirmed bout of rabies—a disease that for most of human history was considered to be fatal in 100 percent of cases.

Today, though, Precious is back just to visit. In the halls of the pediatric ward, where zoo animals cavort in backlit photos, doing their best to dispel the hospital pall, the nurses who treated Precious greet her with delight. She does not remember them at all. But she speaks shyly to each, listening as they recount to her, in turn, their roles in rescuing her. She grows more talkative when describing the life she has resumed back in Willow Creek, in the wilds of California’s Humboldt County. To get in shape for the peewee wrestling season, Precious has been running laps in the long driveway of the farm where she lives with her siblings and grandparents. She also has resumed her pursuit of “mutton bustin’,” a sport in which kids ride rodeo-style on the backs of frantic sheep for as long as they can; at a recent match, she took home the third-place purse of $23.

Precious’ brush with death began with a simple flu-like illness that soon was accompanied by some odd symptoms: head and neck pain, weakness in her legs. At the hospital, a nurse asked her to drink something, but she choked, unable to swallow the fluid. “She looked at me like ‘Grandma, please help,’” her grandmother, Shirlee Roby, recalls. “I could tell this was no damn flu.” Her symptoms were so severe that the local hospital decided to transfer her by helicopter to UC Davis. When the state health department heard the symptoms and the fact that the patient had come from rural Humboldt County, it immediately suspected rabies. Lab tests confirmed the diagnosis: Precious had antibodies against the disease in her blood serum and cerebrospinal fluid, an impossibility in the absence of infection or vaccination. As it turned out, a feral cat had bitten her a few weeks before as she played outside her elementary school. But no one had thought to treat her at the time, and now it was too late for the standard intervention against rabies—a vaccine, administered in multiple shots over the course of two weeks, that allows the body to mount an immune response before the virus reaches the brain. In Precious’ case, it was clear that her brain had already been infected.

Not long ago, the medical response to this grim situation would have been little more than “comfort care”: administration of sedatives and painkillers to ease the suffering. Untreated, this suffering can be unbearable to watch, let alone experience. That telltale difficulty in swallowing, known as hydrophobia, results in desperately thirsty patients whose bodies rebel involuntarily whenever drink is brought to their lips. Soon fevers spike, and the victims are subject to violent convulsions as well as sudden bouts of aggression; their cries of agony, as expressed through a spasming throat, can produce the impression of an almost animal bark. Eventually the part of the brain that controls autonomic functions, like respiration and circulation, stops working, and the patients either suffocate or die in cardiac arrest. A decade ago, the only choice was to sedate them so their deaths would arrive with as little misery as possible.

But today, after millennia of futility, hospitals have an actual treatment to try. It was developed in 2004 by a pediatrician in Milwaukee named Rodney Willoughby, who, like the vast majority of American doctors, had never seen a case of rabies before. (In the US, there are usually fewer than five per year.) Yet Willoughby managed to save a young rabies patient, a girl of 15, by using drugs to induce a deep, week-long coma and then carefully bringing her out of it. It was the first documented case of a human surviving rabies without at least some vaccination before the onset of symptoms. Soon Willoughby posted his regimen online, and he worked with hospitals around the world to repeat and refine its use. Now referred to as the Milwaukee protocol, his methodology has continued to show limited success: Of 41 attempts worldwide, five more patients have pulled through, including Precious, whose recovery has been the most impressive of any victim to date.

Read more at Wired Science

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