According to the World Health Organization WHO , there were only reported cases of polio worldwide in , mostly confined to a handful of Asian and African countries. But if you see something that doesn't look right, click here to contact us! Twice a week we compile our most fascinating features and deliver them straight to you.
Live TV. This Day In History. History Vault. Although polio was the most feared disease of the 20th century, it was hardly the deadliest. In April Scherer headed south to Tuskegee to see the new facility and deliver a precious package. His parcel held contents that were sensitive to temperature swings, and April was one of the few times when Minnesota and Alabama had matching climates.
It contained approximately 30 million HeLa cells. When he arrived at the Tuskegee Institute, a liquid was added to those cells, which then fed 40 other bottles. After four days of incubation, each of these bottles contained 30 million more cells, marking the birth of the HeLa cell factory at the Tuskegee Institute. Inside the Tuskegee HeLa cell factory, cells were grown in a long line of incubators, measured into glass tubes, packaged and then shipped by air to about two dozen medical laboratories all over the country.
HeLa cells died when temperatures broiled around degrees Fahrenheit. While air-conditioning had made the Sunbelt bearable and led to a migration to the South in the s, these sensitive cells were doomed if they traveled in hot cars, waited on hot tarmacs or sat in hot airplane cargo hulls. So the leadership of the NFIP asked Maria Telkes, a physical chemist at New York University, to come up with a packaging solution to keep the cells cool while in transit. Telkes, an expert on thermal insulation, calculated and designed a special shipping container that resembled a Russian doll.
In it, a box covered with insulation sat inside of another box. The inner box contained a can full of the chemical sodium sulfate decahydrate, which rested on top of the glass tubes and kept the cells from overheating. Once placed in these boxes, the cells had to arrive at their destination within 96 hours.
One person drove to airports in Montgomery, Ala. There were many failures in getting the HeLa process right and calls and letters from NFIP officials berated Brown about contaminated samples, low cell output and the arrival of dead cells. Brown, too, was troubled.
But Norma Gaillard, the cell culture supervisor at Tuskegee, kept making improvements and devised an effective procedure that her technicians followed precisely. The team vigorously hunted down the sources of contamination and installed special air conditioners to keep the lab cool and remove the last vestige of dust and humidity.
With time and effort, the technicians eventually exceeded the 10, glass tubes of HeLa cells needed to be shipped in a week. It was a good thing, too, because summer—and polio season—was coming. This trial was a medical logistics effort on a scale never seen before. Now Salk could speed up his research.
Using formaldehyde, he killed the polio virus but kept it intact enough to trigger the body's response. On July 2, , Salk tried a refined vaccine on children who'd already had polio and recovered.
After the vaccination, their antibodies increased. He then tried it on volunteers who had not had polio, including himself, his wife, and their children. The volunteers all produced antibodies, and none got sick. A nationwide testing of the vaccine was launched in April with the mass inoculation of school children.
The results were amazing -- percent prevention -- and Salk was praised to the skies. But suddenly, some cases of the disease were caused by the vaccine and 11 people died. All testing was halted. It seemed that people's hopes were dashed until investigators found that the disease-causing vaccine all came from one poorly made batch at one drug company.
There he rejoined Francis who had since moved to Michigan and spent six years researching the influenzavirus and developing a flu vaccine, work largely supported by the U. The vaccine that they ultimately developed in was a killed-virus vaccine: it contained a formalin-killed strain of the influenzavirus that could not cause the disease but did induce antibodies able to ward off future viral attacks.
Francis and Salk were among the pioneers of killed-virus vaccines. Up to that time attenuated weakened live viruses were used to produce vaccines.
He devoted his efforts to creating a first-class research environment and to publishing scientific papers on a variety of topics, including poliovirus. His work drew the attention of the National Foundation for Infantile Paralysis now the March of Dimes , and he was invited to participate in a research program sponsored by the foundation.
He agreed and took up his assignment of typing polioviruses. In the National Foundation typing program confirmed that there were three types of poliovirus. He also believed that it would be less dangerous than a live vaccine: if the vaccine contained only dead virus, then it could not accidentally cause polio in those inoculated.
One difficulty, however, was that large quantities of poliovirus were needed to produce a killed-virus vaccine because a killed virus will not grow in the body after administration the way a live virus will.
In John Enders, Thomas Weller, and Frederick Robbins had discovered that poliovirus could be grown in laboratory tissue cultures of non-nerve tissue earning them the Nobel Prize in Physiology or Medicine in The work of Enders and his colleagues paved the way for Salk, for it provided a method of growing the virus without injecting live monkeys.
Salk developed methods for growing large quantities of the three types of polioviruses on cultures of monkey kidney cells. He then killed the viruses with formaldehyde.
When injected into monkeys, the vaccine protected them against paralytic poliomyelitis. In Salk began testing the vaccine in humans, starting with children who had already been infected with the virus. He measured their antibody levels before vaccination and then was excited to see that the levels had been raised significantly by the vaccine. In a massive controlled field trial was launched, sponsored by the National Foundation for Infantile Paralysis.
Almost two million U.
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