When I helped run a measles immunization program in West Africa in the 1960s, I learned that in global health small things can spell the difference between a major success and a colossal failure.  LESSONS Nigerians in 1969. Smallpox is gone, but measles is still lethal.  The newly developed measles vaccine had proved to be safe and effective in tests in Upper Volta (now Burkina Faso). But the program to expand benefits of the successful field trial to a larger regional population failed miserably, mostly because of small errors like simple misspellings.  A request for Globaline water-purifying tablets, for example, yielded instead a large shipment of gamma globulin, a huge and costly waste of that human blood product. Other errors resulted in sending refrigerators and other equipment that could not work in the heat of the sub-Saharan region.  Still another error was a miscalculation in the program’s scientific design, guaranteeing that it could not meet its goal to wipe out measles from the region in two years. Nearly 50 years later, measles shots are still needed.  Yet lessons learned from these blunders led to a new program that wiped out smallpox, still the only human disease to have been eradicated from the planet. That success led to greater understanding that disease obeys no national border and that solutions require international cooperation — a recognition that fostered a wide array of global health programs in the decades that followed.  In 1964, I was a year into the Epidemic Intelligence Service, an epidemiology training program, at the Centers for Disease Control and Prevention (then known as the Communicable Disease Center) when Dr. D. A. Henderson, my immediate boss, asked: “How would you like to go to Ouagadougou and Bobo-Dioulasso?” Sure, I said, hurrying to an atlas to check their locations in Upper Volta.  My generation saw childhood measles in abundance. We knew it was a very contagious disease. But few of us realized just how lethal the measles virus could be, particularly in Africa, where death rates in outbreaks ran as high as 25 percent — largely because many patients were already afflicted with malnourishment and parasitic infections.  Smallpox, we later learned, was less contagious. And it was highly preventable, thanks to the vaccine first developed by the British doctor Edward Jenner in 1798. Yet that viral disease had killed and scarred hundreds of millions of people around the world. While smallpox had disappeared from the United States by 1949, in Africa I saw many more cases of it than of heart attacks.  The West African measles immunization program in 1964 owed to a combination of medical advances, business and politics. After Merck, the American pharmaceutical company, completed field trials of its new measles vaccine in Upper Volta, the company’s sales force convinced that country and seven neighbors (the newly independent nations that had once made up French West Africa) that their children should receive it as a reward for Upper Volta’s participation in the original trials.  But the program soon became a political battleground. Some critics considered a French vaccine superior to the American one; the United States government, heavily influenced by business interests, insisted on American products.  The United States bought enough jet guns to inject Merck vaccine into the arms of 25 percent of children younger than 3 in the eight West African countries for two consecutive years. The Agency for International Development reasoned that this would be enough to stop transmission of the virus, despite lack of any scientific evidence, and the fact that officials failed to include newborns in calculating the estimated target population.  The agency assumed that what would work in the United States should also work in West Africa. But its officials had little if any appreciation for the vast differences between the developed and developing worlds, or the logistical challenges of working in sub-Saharan Africa. For example, the measles vaccine had to be kept cold and out of the sun, because heat and ultraviolet light could destroy it. That was a challenge in sunny West Africa, where temperatures often were above 100 degrees and refrigeration was scarce. Officials at the agency, U.S.A.I.D., thought they could overcome those problems by sending butane-gas-powered refrigerators and tinfoil to wrap around the vaccine vials.
Medicine might never have achieved its greatest triumph to date â eradicating smallpox â if small errors had not been made in a measles immunization program.