Pandemic Reads 1
House on Fire: The Fight to Eradicate Smallpox
Dr. William Foege’s “House on Fire” is an engaging and concise 200 pages on the barriers and circumstances of eradicating smallpox. Foege is the perfect storyteller — according to Wikipedia he is “credited with ‘devising the global strategy that led to the eradication of smallpox’ ” and afterward he served as Director of the CDC and received the Presidential Medal of Freedom.
Historical Context
The book covers some historical cases of smallpox, and early understandings of immunity. From other reading, this disease emerged roughly around 3–4,000 years ago, relatively recent but still early in recorded history. Variolation (deliberately exposing people to small and less-active smallpox scabs rather than natural infection) was developed in China (with people sometimes snorting powdered pox) and spread to India and Africa. In the 1700s, British travelers encountered it in Turkey and the policy spread to the British military. During the winter break in fighting at Valley Forge, George Washington made the decision to follow suit to avoid letting the British soldiers getting an edge.
Dr. Foege recounts a conversation with a traditional healer in Nigeria who practiced variolation, and understood the effectiveness in terms of probability of harm or immunity from getting infected. Despite these local experts, communities tended to forget smallpox outbreaks and get re-infected every 10 years, when their children had no immunity.
The immunity gained from cowpox was observed in 1796. Methods gradually modernized, especially in the US and Europe. In 1947, a small outbreak in New York City was stopped in its tracks by a massive response — 5 million New Yorkers were inoculated in two weeks. In other parts of the world smallpox was persistent and recurring… until in the 1960s it was suddenly possible to manufacture modern vaccines in the remaining affected countries, and inject everyone village by village. Then Dr. Foege piloted a new public health strategy which finally stopped smallpox from reoccurring in Nigeria and India.
Road to Public Health Hero
The early parts of Dr. Foege’s career lead to being the perfect person to coordinate smallpox response. When his family moved to a new town he had a leg injury which the local pharmacist mistook for a permanent disability and offered him work. He had a job building firebreaks to protect forests (this does become relevant later). In med school his advisor was the county public health director. When he started his own public health work, he was called to Navajo Nation to investigate a potential smallpox case and trace contacts. This was an unusual case, so he was asked to make a presentation at the CDC. That presentation got him in contact with experts who were looking for epidemiologists in India and Nigeria.
In Nigeria, Dr. Foege explained how shortages of vaccine led him and other international doctors to change their process. Some doctors would dilute their mass vaccination program, but his team instead scaled up their immediate personal contact tracing process, making ‘firebreaks’ for anyone who came near an infected person. This was surprisingly effective, but counterintuitive to many public health experts and politicians.
Eventually the tactic (and new, reliable, locally-manufactured injections) broke the long stalemate of mass vaccination programs, and a similar surveillance and contact-tracing program stopped smallpox from spreading in India, one of the last holdouts, within only 20 months.
Dr. Foege’s role in India was more managerial, so this part of the book covered more political infighting, international relations, logistics, tactics to supervise workers. As someone who’s worked at NGOs, I preferred the first half of fieldwork stories, but you might prefer the second half if you are a manager.
Vaccines exist; biology determines success
Something which I didn’t understand prior to this book is how smallpox could be eradicated in the 1960s and 1970s, and that achievement be unmatched since. In Nigeria, Dr. Foege implemented contact-tracing for smallpox, but continued doing mass vaccinations for measles, and measles continues to exist today. Why?
This year we’ve gotten more familiar with R0, a measure of how exponentially contagious a disease is. Measles is one of the most contagious diseases known. Smallpox was once thought to be super-contagious, but as the science and hygiene got better, it was clear you could keep infectiousness to a six foot radius. You could vaccinate the patient and their contacts, even after infection, and improve their survival rate. Infected patients were obvious and the symptoms were distinctive. There were no asymptomatic cases of smallpox.
‘Vaccinate everyone’ was intuitive, but it couldn’t reach perfection. Humanity won by discovering and understanding smallpox’s weaknesses… while other diseases keep going on because they don’t have those same weaknesses.
Systems matter, too
There’s an interesting phrase in the book:
You get what you inspect, not what you expect
After starting active surveillance in India, Dr. Foege’s team found 10 times as many infections as were typically reported. These numbers made political leaders angry, but it was the truth.
It was natural for foreign experts to shake their heads at these hidden numbers, but to the afflicted it was perfectly logical — they recognized smallpox and knew that the hospital couldn’t cure it.
Part of the problem in India was convincing the people that it was not another numbers game. The national health program had grown complacent. To keep the numbers up, health workers would visit the same schools year after year rather than searching further afield or finding active outbreaks. Active surveillance, top-down division of workers, and supervisor tactics finally changed how public health worked.
Toward the end of the program, public health officials began offering rewards for news of new outbreaks. The rewards program had to be structured carefully to verify reports and residency (some smallpox patients had been moved to other towns to report new outbreaks). When rewards increased in value and still went unclaimed in more cities, it became much more real to any skeptics and would-be winners: you really can’t find this anymore. It’s over.
From the conclusion of the book
In medicine, the medical practitioner is obliged to apply the best knowledge of the times to each patient. In public health, the obligation is to apply the best knowledge to the entire human community. The purpose of public health is to promote social justice.
