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The Eradication of Smallpox

The Eradication of Smallpox . Ashley Nkadi April 4, 2013. The Gameplan …. (Start itching!). What is Smallpox? History of Smallpox Evolution of the Smallpox Vaccine The motion to eradicate smallpox Smallpox in Southern Africa. What is Smallpox?.

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The Eradication of Smallpox

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  1. The Eradication of Smallpox Ashley Nkadi April 4, 2013

  2. The Gameplan…. (Start itching!) • What is Smallpox? • History of Smallpox • Evolution of the Smallpox Vaccine • The motion to eradicate smallpox • Smallpox in Southern Africa

  3. What is Smallpox? • Smallpox is caused by infection with the variola virus. Two variants exist: Variola Major (severe and most common) and Variola minor (less common and less severe). It has a fatality rate of 30%. • Four Types of Variola Major Smallpox: • Ordinary: Most Frequent, accounts for 90% of cases • Modified: Mild, usually occurs in previously vaccinated people • Flat: Rare and very severe • Hemorrhagic: Rare and very severe Variola Virus

  4. What is Smallpox? • symptoms: Fever, headache, severe fatigue, severe back pain, vomiting, diarrhea initially. Later, rash, legions, raised bumps, fluid-filled blisters, and scabs. • transmission: Transmission occurs through inhalation ofairborne variola virus occurring from prolonged face-to-face contact with an infected person. Can also be transmitted via bodily fluids or contaminated objects.

  5. Incubation Period (Days 1-12): Occurs after exposure to virus, no symptoms are not present yet, and person is not contagious Prodrome (preeruptive) Stage (Days 12-15): First symptoms, including: fever, Pustular Rash (Days 20-25): Bumps become aches and vomiting Early rash (Days 16-19): Rash begins in mouth/throat/tongue, person is most contagious pustules that are raised, round, and firm to the touch. Pustules and Scabs (Days 25-28): Pustules and sores scab, person is still contagious Resolving Scabs (Days 29-34): Scabs begin to fall off, leaving marks on the skin that will become pitted scars. Once all scabs fall off the person is not contagious.

  6. Spread of Smallpox • Smallpox present as early as 1145 BC – Earliest credible case in Egyptian mummy, Ramses V

  7. Smallpox: Effects on History

  8. Vaccine • Attempts to inoculate against smallpox started as early as 1000 BC by having smallpox scab powder put in the nostril • (1796) Edward Jenner inoculated an eight-year-old with matter from a cowpox sore on the hand of milkmaid. After the boy recovered, Jenner inoculated him with matter taken from a fresh human smallpox sore. No disease developed. First Vaccine • From his initial findings advancements were able to be made such as: non-humanized vaccines, addition of glycerin, air dried vaccines, and freeze dried vaccines.

  9. Eradication Initiaitve • On January 1, 1967, the World Health Organization launched the Intensified Smallpox Eradication Programme • At the time, smallpox was endemic in countries or territories in Asia, Brazil, and all regions of Africa. • The plan: Mass vaccination of susceptible persons in endemic countries and the development of a system to detect and monitor smallpox cases and contain outbreaks. • Requirements: High volume production of potent, reliable vaccines and an efficient, inexpensive means of delivering the vaccine. Participation from countries was also vital.

  10. Eradication Initiative • Three innovations facilitated the eradication: • Freeze-dried vaccines • Had the potency and stability needed for mass vaccination and could be mass produced using minimal resources. • Jet injector • Could do over 1,000 vaccinations in an hour, but was later deemed too expensive. • The bifurcated needle • Required less vaccine material for each dose, and was easier than previous methods.

  11. The beginning of Smallpox in Southern Africa • Southern Africa remained free of smallpox until relatively late • In 1713, smallpox was introduced to Capetown via the dirty laundry of the Dutch • Called “kaffir-pox” • The KhoiKhoi tribe (“hottentots) were reduced to less than 10% of their original populations by smallpox. • Slave trade and caravans facilitated the spread of smallpox

  12. Smallpox in South Africa • Persistence of endemic smallpox in South Africa is due to the fact that for 50 years the predominant type of smallpox was a form of variola minor which was less severe and had a low fatality rate. •  Only 17 deaths from 1922-1944 and only 13 deaths from 1953-1971 • Response: Intense house-to-house vaccine campaign in 1970 • Global Commission agreed on 17 April 1979 that smallpox eradication had been achieved in South Africa.

  13. Smallpox in Botswana • General Outline: • 1930-1942: Smallpox was endemic. People used traditional treatments and rarely accepted vaccines. • 1943-1964: Smallpox became pandemic. People started readily accepting vaccines. • Now, for the specifics…

  14. Smallpox in Botswana • Factors that attributed to the delayed delivery of vaccines to Botswana inhabitants: • Unemployment: Labor migrations aided the spread of smallpox. In addition, illegal workers would dodge vaccinators in fear that they would be vaccinated then sent back or arrested • Traditional Treatments: People would refuse vaccines in favor of traditional treatments instead, which were often ineffective. Or people would use both, which would decrease the effectiveness of the vaccine.

  15. Smallpox in Botswana • Vaccination campaigns were started to fight smallpox, however there were several roadblocks: • (1941) New smallpox strains from India were introduced due to increased intercommunication from WWII. This caused reinfections of vaccinated persons. • (1943) Heavy rains made roads impassable to vaccine vans, and encouraged people cultivate their farm lands rather than get vaccinated • Tropical conditions had an adverse affect on the potency of the calf lymph vaccinewhich led to recurrences and relapses

  16. Smallpox in Botswana • Finally a breakthrough occurred in the late 1950s • The new dried form of vaccine was created that was resistant to heat and therefore more effective. • The mass spread of the disease greatly increased people’s willingness to receive vaccines • Finally: noting that there had been no evidence of confirmed smallpox since 1973 or of suspected cases since 1974, the Commission certified that smallpox had been eradicated from Botswana.

  17. Smallpox Eradicated • In 1977, the last case of smallpox was reported in Somalia. • 5/8/1980: The World Health Assembly accepted the WHO Global Commission’s recommendation and declared the world free from smallpox.

  18. References • http://www.historyofvaccines.org/content/timelines/smallpox • http://www.bt.cdc.gov/agent/smallpox/overview/disease-facts.asp • https://extranet.who.int/iris/restricted/bitstream/10665/39485/1/9241561106.pdf • http://archive.lib.msu.edu/DMC/African%20Journals/pdfs/PULA/pula017001/pula017001003.pdf

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