Yellow Fever Vaccine

  • Medicine & Health
  • 1937

Yellow fever, one of the most feared diseases in America, ravaged port towns and nearby communities throughout the eighteenth and nineteenth centuries. In addition to the human toll, international trade was often badly disrupted by its quarantines. While no medical consensus existed on the origins of yellow fever, many believed the disease originated in the tropics and was carried by ships involved in the slave trade in the West Indies or by transports returning soldiers from the Spanish-American War.

At one point President Grover Cleveland established a special commission to investigate possible causes and treatments of the disease; on both counts, no effective knowledge existed. Some scientists then believed that the disease was bacterial and that they had created the first “vaccines” against the malady. The commission declared them mistaken, that bacteria did not appear to be the cause but that the disease was transmitted by mosquitoes.

Meanwhile tens of thousands of Americans were dying in the early decades of the twentieth century. After the Panama Canal opened in 1912, exposing additional communities to the affliction, the Rockefeller Foundation launched an all-out three-decade campaign to eradicate the disease. In 1918, it sent a team to Ecuador to study potential causative agents. An initial claim that a vaccine had been discovered by Rockefeller researchers was disproven in 1926. At that same time, the Rockefeller Foundation set up another research station in Nigeria. Scientists working amidst the tension of its dangerous environment learned how to use rhesus monkeys to test infection and immunity to the disease. But three of the lead researchers working for the foundation died in the process.

A little later, the Rockefeller Institute set up a lab in New York to continue its yellow-fever research using animals. Director Simon Flexner proceeded hesitantly, given the loss of life already experienced in the institute’s work. Strict isolation policies were used to reduce the danger. Even still, many of the lab staff contracted the disease over the next two years, and a 1931 report from the institute noted that 32 cases of the disease acquired in eight labs had recently resulted in five deaths.

In 1931, Rockefeller Institute researcher Dr. Bruce Wilson volunteered to be injected with a new vaccine developed in mice. Held under strict isolation and supervision, he did not become ill and developed immunity. The vaccine required serum from already-immune humans, which meant it could not be produced in volume, but at least there was finally a means of protecting lab staff.

In 1937, foundation scientists finally announced a successful mass-producible vaccine. Between 1940 and 1947, the Rockefeller Foundation distributed more than 28 million doses of the vaccine. Lead researcher Max Theiler was awarded the Nobel Prize in medicine in 1951 for this work. The Rockefeller vaccine continues to be the most effective and affordable prevention strategy for yellow fever.