The Eradication of Smallpox Ashley NkadiApril 4, 2013

The Gameplan…. (Start itching!)

What is Smallpox?History of SmallpoxEvolution of the Smallpox VaccineThe motion to eradicate smallpoxSmallpox in Southern Africa

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 casesModified: Mild, usually occurs in

previously vaccinated peopleFlat: Rare and very severeHemorrhagic: Rare and very severe

Variola Virus

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 of airborne variola virus occurring from prolonged face-to-face contact with an infected person. Can also be transmitted via bodily fluids or contaminated objects.

What is Smallpox?

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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,

aches and vomiting

Early rash (Days 16-19): Rash begins in mouth/throat/tongue, person is most contagious

Pustular Rash (Days 20-25): Bumps become

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.

Spread of Smallpox Smallpox present as early as 1145 BC – Earliest credible case in

Egyptian mummy, Ramses V

Smallpox: Effects on History

YEAR EVENT RESULT / CORRELATING

EVENT108 Large-scale

Smallpox EpidemicFirst stages of the

decline of the Roman Empire

1520 Smallpox introduced to the

New World by Spanish and Portuguese

Fall of the Aztec and Inca empires

1763 Speculation: The British give

smallpox infected blankets to Native

Americans

Devastation of Native American

population

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.

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.

Eradication InitiativeThree 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 INJECTORCould 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.

The beginning of Smallpox in Southern

AfricaSouthern Africa remained free of smallpox

until relatively late In 1713, smallpox was introduced to

Capetown via the dirty laundry of the DutchCalled “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

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.

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…

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.

Smallpox in BotswanaVaccination 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 vaccine which led to recurrences and relapses

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.

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.

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