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Experts Urge Mass Dog Vaccination to Eradicate Rabies

Some rabies infections may not be lethal, but be especially wary of dog bites

Her physician, Rodney E. Willoughby, Jr., a pediatric infectious disease specialist, had never seen a case of rabies. He scoured the scant medical literature and found a gleam of hope: an experiment in which keeping rats anesthetized somehow allowed them to recover from a rabies infection. The rabies virus disrupts the usual electrical and chemical communication between neurons in the brain stem, which in turn loses its ability to regulate the heart and lungs. Perhaps, Willoughby reasoned, effectively silencing the brain with general anesthetics—while keeping the patient alive with a heart-bypass machine and mechanical ventilator—would buy the immune system enough time to destroy the virus. He decided to try it.

Against all odds, the therapy succeeded. Giese survived the viral storm, although she suffered some brain damage and spent two years relearning how to speak, stand and walk. She graduated from college in 2011 and now works as an animal caretaker and motivational speaker. Meanwhile Willoughby has continued to tinker with his intervention. But even he admits that the procedure is not a viable option for most clinics, because it demands so many resources.

In fact, some researchers wonder whether the Milwaukee protocol is truly effective at all. These naysayers have proposed that the real secret to at least some patients' survival is the fact that they were bitten by animals other than dogs that transmit either very tiny doses of rabies virus or strains that the human immune system can clear on its own.

Canine Carriers

While doctors debate whether the Milwaukee protocol works, public health experts agree that the most effective way to deal with rabies is to stop the disease at its source. Globally, domesticated and stray dogs are responsible for nearly all the 55,000 rabies deaths every year, according to the World Health Organization. The burden tends to fall most heavily on people (especially children) in rural areas, which have limited access to the rabies vaccine given annually to more than 15 million people to try to prevent the illness after someone has been exposed.

That leaves preventing rabies in dogs as the best option for reducing the number of deaths in humans. On a purely economic basis, mass dog vaccination certainly makes sense. Canine vaccines are not only less expensive than injections for people, they are far less expensive than critical care treatment of a human rabies case. But it can be difficult, politically speaking, to get anyone to pay attention to the health and welfare of dogs when people's needs remain so much more obvious in so many parts of the world, says Charles Rupprecht, formerly rabies chief at the U.S. Centers for Disease Control and Prevention and now director of research at the nonprofit Global Alliance for Rabies Control (GARC). “Medicine addresses human health issues, and agriculture addresses livestock—dogs are neither,” he says. “It takes vision to see that this is a public health problem: you vaccinate dogs, human rabies cases come down, and you can put your public health dollars toward other goals.”

Despite the daunting numbers—by one estimate the world count of stray dogs is 375 million—GARC researchers believe that dog vaccination programs are logistically feasible, and they have established pilot projects in Africa and Asia (some with support from the Bill & Melinda Gates Foundation). On the Philippine island of Bohol (human population: 1.3 million), researchers vaccinated an estimated 70 percent of the dog population. Before 2007 about 10 people died from rabies each year; since 2008 only one person has died of the disease.

Persuading people to vaccinate their pets is not always easy. Dealing with stray dogs is even more challenging. Because of a relentless rise in the number of rabies deaths in rural China, mostly in the south, that country has organized several mass killings of dogs, which disease-control experts and animal-rights activists have harshly criticized. Even if the cullings are effective in the short term, the stray populations inevitably rebound, as will the virus. Meanwhile the popularity of keeping dogs as pets—around half of which may be unvaccinated—continues to increase as Chinese workers become more prosperous.

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