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So I went down a rabbit hole of human challenge studies through history, there's some Good, some Bad and some Ugly.
1/. Smallpox 1796 - English Edward Jenner tested the world’s first #vaccine by exposing his gardener’s 8-year-old son to cowpox and then smallpox.
1/. Smallpox 1796 - English Edward Jenner tested the world’s first #vaccine by exposing his gardener’s 8-year-old son to cowpox and then smallpox.
2./ Yellow Fever 1898 - The U.S Army established a commission led Walter Reed to figure out how YF spread and how to stop it. Reed and 3 colleagues designed a human challenge study to test a leading theory of yellow fever transmission: mosquito bites.
2./ During the experiment, the scientists first mosquitoes to bite YF patients so the insects would pick up the disease. Then, they the mosquitoes were allowed to bite healthy volunteers. When volunteers fell ill, Reed analysed blood samples for the disease causing agent.
2./ In the first round of experiments, 11 volunteers got mosquito bites. Two fell ill, and survived. The 3rd man to fall ill, Jesse W. Lazear, was one of the scientists running the study
. He was bitten by accident and died of yellow fever 12 days later.
. He was bitten by accident and died of yellow fever 12 days later.
2./Reed considered ending the study after the death of his colleague but didn't. By 1901, Reed had demonstrated that mosquitoes could transmit YF. Inoculation of more volunteers w filtered blood from YF patients identified a virus as the causal agent -1st human virus discovered.
2./ Once the YF virus was indentified, William Gorgas and Juan Guiteras established an inoculation station for a new round of human challenge studies in Havana.They hoped to learn how to induce light cases of YF with mosquito bites in order to give people immunity.
2./ More than 20 volunteers signed up for the first experimental inoculations in 1901, including t, a military nurse named Clara Maass. Maass was bitten 5x w/developing YF. Her 6th mosquito bite proved fatal.
2./ She and 2 other volunteers were infected with a particularly virulent strain of the virus all three died in August of 1901. The dark legacy of the infamous Havana experiments endure to this day.
3./ Syphilis -1932: Another infamous challenge study that relied on a vulnerable population is the Tuskegee Syphilis Study. The U.S. Public Health Service recruited about 600 poor AA men from around Tuskegee, Alabama, for a study of how syphilis worsens over time.
3./ About 2/3 of the men had syphilis, but were given a phony diagnosis of "bad blood" by Drs. The men were persuaded to join the study in exchange for free meals, hospital access and treatment for “bad blood” and other unrelated conditions.
3./ The scientists also provided participants a burial stipend that would be paid to their survivors after their deaths. Only about 1/2of the men with syphilis received the treatment available in the 1930s: doses of toxic arsenic and mercury.
