Friday, June 24, 2011

SMALLPOX, GONE BUT NOT FORGOTTEN

How a Scourge Was Eradicated
What to do when family members insist on visiting an infectious relative? Vaccinate them at the door.

House on Fire
By William H. Foege 
(California, 218 pages, $29.95)
Smallpox, one of the deadliest diseases in human history, was eradicated more than 30 years ago by an army of public-health warriors who chased the virus across the globe, down to its last patient. The effort was a vast international project; achieving the goal took more than a decade. And it would have been a lot harder, and taken a lot longer, had necessity not forced William Foege to improvise at a critical moment, making a chance discovery. (click below to read more)


The American medical missionary was working as a consultant for the World Health Organization's newly intensified smallpox-eradication program in eastern Nigeria in late 1966. As he and his colleagues were preparing to launch a mass-vaccination campaign, they learned of a smallpox outbreak in a remote village. They faced a quandary. Protocol called for everyone in the area to be vaccinated. But the recently formed smallpox team was still waiting for supplies. They didn't have enough vaccine.
The team members asked themselves: "If we were smallpox viruses bent on immortality, what would we do to extend our family tree?," Dr. Foege recalls in "House on Fire," his rich, suspenseful memoir of this historic public-health campaign. The virus, they concluded, would find the nearest susceptible person. "Our task, then, was not to vaccinate everyone within a certain range but rather to identify and protect the nearest susceptible people before the virus could reach them."
Missionaries within a radius of about 30 miles were contacted by radio; the team asked them to send runners to every village and report any signs of smallpox. Vaccinations were given to everyone in the four villages where the runners identified cases, as well as to the residents in three other villages where missionaries said the patients and their families had traveled. The outbreak was quickly stopped in its tracks. The smallpox warriors had "built a fire line" around the virus, Dr. Foege writes. Thus was born a strategy that would become central to quelling smallpox.
The title of "House on Fire" comes from a young Indian physician who compared the new "surveillance and containment" approach, as Dr. Foege calls it, to pouring water on a burning house rather than on surrounding houses in case the fire spreads. Mass vaccination—a huge undertaking—had been made possible by new vaccine technologies, but the more targeted approach, Dr. Foege says, eventually became the main weapon.

After the strategy's success in West and Central Africa, it was later put to an even tougher test in densely populated Bihar, India. In the first four months of 1974, India reported more than 67,000 smallpox cases, with more than two-thirds of them in Bihar. By identifying and then dousing thousands of outbreaks, the smallpox warriors began to reverse the tide by May of that year. A year later—20 months after the effort began—India reported its last case of smallpox. By 1980, smallpox—having killed countless millions across the centuries—was declared completely wiped out world-wide.
While "House on Fire" isn't the first history of the smallpox-eradication program, it is perhaps the most personal. Dr. Foege, a charismatic public-health leader who went on to head the Centers for Disease Control and Prevention for six years beginning in 1977, bounces the reader along with him in his jeep, on motorbikes over rugged terrain and on bustling trains. "You can smell smallpox before you enter the patient's room," he writes, likening the odor to that of a dead animal and describing the "catatonic" demeanor of patients trying to avoid painful movement.
The drive to snuff out smallpox was conducted even as civil war erupted in Nigeria and as political opposition to the targeted-vaccination efforts mounted in India when eradication seemed slow to come. Executing the campaign required patience and precision. It took hundreds of training sessions in India just to teach health workers how to search for smallpox cases. Another challenge was the Indian tradition of friends and relatives visiting smallpox patients. Barring the visits wasn't an option—the goddess of the disease would be offended. The solution: stationing vaccine-equipped watch guards at patients' houses and vaccinating every visitor. At the peak of the 1974 smallpox season in India, between 50,000 and 100,000 guards were posted in response to 8,000 outbreaks.
Given Dr. Foege's vital public-health role, it would have been interesting to hear more from him about how the lessons of smallpox eradication might apply today to attempts to extinguish polio or control malaria. And he is silent on a lingering debate: what to do about the last known vestiges of the live smallpox virus, housed in labs at the Centers for Disease Control and at a Russian research institute. Proponents of destroying the virus want to ensure that the disease is banished forever; opponents maintain that the samples are needed to make vaccines in the event of an unforeseen outbreak. The matter is so divisive that the World Health Organization last month delayed, not for the first time, a plan to destroy the stocks. The question will be revisited in 2014.
Dr. Foege does reflect at times on lessons learned, even dispensing advice on how to conduct a mass vaccination campaign to combat a smallpox bioterrorism attack. As enthusiastic as he is about the surveillance-and-containment strategy, he is careful to note that it is not suited for every disease. Almost everyone who was infected with smallpox developed telltale pockmarks, making the virus easy to track. It didn't spread as easily as some other infectious diseases. And unlike malaria, it wasn't transmitted by animals or insects. "The smallpox eradication story contains many lessons," he writes, "but giving up mass vaccination as a methodology for other diseases is not one of them."
"House on Fire" shows what can be accomplished when governments and thousands of health workers focus on a single objective. When he travels to India these days, Dr. Foege says, he searches faces on the street, looking for smallpox scars. On anyone under age 35, he can't find any.

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