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. In other areas of the country children who did not receive any vaccine were carefully observed.
Accomplishing this required the assistance of the pharmaceutical industry, and well-known companies like Eli Lilly and Company, Wyeth Laboratories, and Parke, Davis and Company agreed to make the new vaccine.
In the meantime a live-virus vaccine for polio was being developed by Albert Sabin. Sabin, like many scientists of the time, believed that only a living virus would be able to guarantee immunity for an extended period.
Sabin was born in in Bialystok, Russia now part of Poland. At the age of 15 he emigrated with his family to the United States. After Sabin graduated from high school in Paterson, New Jersey, his uncle agreed to finance his college education, provided that Sabin studied dentistry.
After two years preparing for dentistry at New York University, Sabin switched to medicine, having developed an interest in virology. In doing so he lost his financial support, but odd jobs and scholarships enabled him to continue his education. While at medical school Sabin spent time researching pneumonia, developing an accurate and efficient method of determining its cause in individual cases—either pneumococcus or virus.
He received his MD in and, after completing his internship, traveled to the Lister Institute of Preventative Medicine in London to conduct research. A year later he returned to the United States, having accepted a fellowship at the Rockefeller Institute for Medical Research. There Sabin developed an interest in poliovirus. In he and a colleague were able to grow poliovirus in brain tissue from a human embryo. Polio reached epidemic proportions in the early s in countries with relatively high standards of living, at a time when other diseases such as diphtheria, typhoid, and tuberculosis were declining.
Indeed, many scientists think that advances in hygiene paradoxically led to an increased incidence of polio. The theory is that in the past, infants were exposed to polio, mainly through contaminated water supplies, at a very young age.
However, better sanitary conditions meant that exposure to polio was delayed until later in life, on average, when a child had lost maternal protection and was also more vulnerable to the most severe form of the disease.
Because of widespread vaccination, polio was eliminated from the Western Hemisphere in In , it continues to circulate in just Afghanistan and Pakistan, with occasional spread to neighboring countries. Vigorous vaccination programs are being conducted to eliminate these last pockets.
Polio vaccination is still recommended worldwide because of the risk of imported cases. In the United States, children are recommended to receive the inactivated polio vaccine at 2 months and 4 months of age, and then twice more before entering elementary school. Contagious Nature of Polio Discovered. In , Swedish physician Ivar Wickman suggested that that polio was a contagious disease that could be spread from person to person. March of Dimes Is Born.
A huge fundraising effort began in when entertainer Eddie Cantor suggested on the radio that people send dimes to the White House to help fight polio. The manned torpedo, also known as the The antiwar movement had initially given Nixon a chance to make good on his campaign promises to end the war in On March 26, , President Thomas Jefferson attends a public party at the Senate and leads a diverse crowd in consuming an enormous loaf of bread dubbed the mammoth loaf.
The giant bread was baked to go with the remnants of an enormous block of cheese. Two years earlier, a Sign up now to learn about This Day in History straight from your inbox. This Side of Paradise is published, immediately launching year-old F. Scott Fitzgerald to fame and fortune. Paul, Minnesota, to a once well-to-do family that had Responding to a call, police raid the Philadelphia home of Gary Heidnik and find an appalling crime scene. A fourth woman, Josefina During a radio broadcast dealing with a Senate investigation into communists in the U.
Lattimore soon became a central figure in the Live TV. This Day In History. History Vault. Art, Literature, and Film History.
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