Polio

• Poliomyelitis


  An infectious disease caused by an enterovirus C belonging to the Picornaviridae family
• Polio virus

  • Single stranded RNA virus
• Polio has caused paralysis and death for much of human history
• For centuries polio was endemic throughout the world and rarely caused epidemics
• Epidemic outbreaks were unknown before the 20th century because the virus was endemic in communities and infants were exposed to the virus very early while receiving antibodies from their mother's milk
• Early evidence of poliomyelitis

  • Egyptian hieroglyphics showing priest with wooden staff and club foot
  • Middle Kingdom Egypt 1300BC
  • Ancient Egypt 3700BC
  • Egyptian mummy with probable polio
  • 1580 - 1350BC - priest Ruma with a withered leg and equinus foot
  • Middle Ages 1559 - painting by Pieter Bruegel showing a crippled begger
• First known description of poliomyelitis by Underwood

  1789
• First documented epidemic of poliomyelitis in the island of St. Helena


  1834
• First description by Dr. Benjamin Duchenne of the pathological process in poliomyelitis


  1855
• Poliomyelitis lesions

  Destruction of the anterior horn cells of the spinal cord and the brain stem, causing a lower moto neuron type of paralysis with flaccid paralysis but normal sensation
• Poliomyelitis is a very painful disease, with muscles in the lower limb much more affected than the upper limb
• Treatment in the early convalescent stage is mainly directed at treating muscle pain and spasm and to preventing these deformities
• Clean Disease - "Middle Class Plague"


  In rural communities with primitive sanitation facilities, poliovirus circulated freely and infants experienced sub clinical immunizing infections whilst still protected by maternal antibodies. In communities with improved sanitation, children were likely to encounter the virus for the first time at a later age and without the protection of maternal antibodies, putting them at far greater risk.
• The 20th century was a game changer for polio, with epidemics beginning in the early 1900s and up to half a million people dying around the world each year of polio
• Dr. Karl Landsteiner and Dr. Erwin Popper managed to induce polio in old world monkeys, providing the first animal model


  1908
• First large epidemic/pandemic of poliomyelitis, with 27,000 people infected and 6,000 deaths in the US


  1916
• Growth of the virus in tissue culture by Dr. John Enders


  1949
• 3 types of polio virus isolated and identified


  1951
• First large scale trial of Salk vaccine (killed vaccine) by injection


  1954
• First general use of Sabin vaccine (live attenuated vaccine) by mouth


  1958
• Franklin D. Roosevelt

  3 term president who developed polio in 1921, was paralyzed from the waist down, and could not walk without a body brace. He was a great promoter of philanthropy for polio.
• Nationwide crusade against poliomyelitis

  1. Began at Warm Springs, GA, a spa where FDR first went in 1924, seeking the therapeutic effects of the warm spring waters

  2. Roosevelt purchased the whole property in 1926 and established the nonprofit Warm Springs Foundation

  3. During the Great Depression, the GA Warm Springs Foundation, in need of funds, started to appeal to the general public

  4. In January 1938, President Roosevelt established the National Foundation for Infantile Paralysis

  5. Comedian Eddie Cantor coined the phrase "March of Dimes" appealing to radio listeners all over the country to send their dimes directly to the White House

  6. The campaign proved to be hugely successful
• The National Foundation for Infantile Paralysis officially changed its name to the March of Dimes in 1979
• David Bodian publishes the classic study of the pathology of poliomyelitis


  1942
• MacFarlane Burnet and Jean McNamara identify 3 serotypes of poliovirus 1, 2, and 3


  1948
• Thomas Weller and Frederick Robbins and John Enders succeed in growing poliovirus in cell culture, providing the foundation for the development of vaccines against polio


  1949
• Development of polio vaccines

  1. 1948 - With funding from the March of Dimes, Dr. Jonas Salk was able to grow the 3 known types of polio virus in his lab and eventually to develop an experimental killed-virus vaccine

  2. Summer of 1952 - Dr. Salk tested the vaccine on children who'd already recovered from polio

  3. Next step was to try it on volunteers who had not had polio - including himself, his wife, and their children

  4. 1962 - An oral polio vaccine, developed by Dr. Albert Sabin, with funding from the March of Dimes, was licensed
• Iron Lung


  Ventilators used to keep polio victims alive by assisting with respiratory failure caused by paralysis of the intercostal muscles and diaphragm
• Sister Kenny


  Australian nursing sister who became world famous for her revolutionary treatment of infantile paralysis, involving the application of hot packs and the exercising of children's limbs
• Many innovative techniques in rehabilitative medicine were developed in the Sister Elizabeth Kenny Institutes, leading to physical therapy
• Salk's Vaccine


  An inactivated virus vaccine that was very effective in preventing important clinical signs of polio disease and was immediately put into widespread use by 1954
• The inactivated polio vaccine (IPV) produces a strong immunity in the blood, protecting vaccinated individuals from polio
• Sister Elizabeth Kenny

  • Her unorthodox procedures were "dangerous, damaging, costly, and cruel"
  • She went to the US of America in 1939 with Queensland government assistance
  • Formal experiments there proved her treatments resulted in a much higher recovery rate than any other method
• Sister Elizabeth Kenny Institutes

  • Established throughout the USA
  • Many innovative techniques in rehabilitative medicine were developed in these institutes
• Physical therapy


  Developed from the techniques in the Sister Elizabeth Kenny Institutes
• Dr. Jonah Salk


  Believed that an inactivated virus techniques similar to the method used for the influenza vaccine would yield a safe and effective poliovirus vaccine
• Development of Salk's Vaccine

  1. Spring of 1952 - After 2 years of development, Salk began experimental trials of his killed virus vaccine

  2. Large scale trials were begun in 1954
• Salk's Vaccine


  • Very effective in preventing important clinical signs of disease
  • Immediately put into widespread use by 1954
• Inactivated polio vaccine (IPV)


  • Produces a strong immunity in the blood, protecting vaccinated individuals from acquiring paralytic poliomyelitis
  • Not so good at stopping virus replication in gut and shedding in feces
  • Immunity was not life long
• Polio vaccine was funded by philanthropy without government oversight of manufacturing