Eradication of smallpoxEradication of smallpox—a global first —a global first

(Polio is next—if we don’t (Polio is next—if we don’t abandon the plan!)abandon the plan!)

Global eradication of smallpox: Global eradication of smallpox: a victory of the Cold Wara victory of the Cold War

1958, Minneapolis: Russia challenged World 1958, Minneapolis: Russia challenged World Health Assembly to begin global eradicationHealth Assembly to begin global eradication

1966, LBJ: International Cooperation Year, 1966, LBJ: International Cooperation Year, support global eradicationsupport global eradication

1979: eradication achieved1979: eradication achieved Cost: $300 million, 21 year campaign (1958-Cost: $300 million, 21 year campaign (1958-

1979), plus contributions of national and local 1979), plus contributions of national and local health authorities.health authorities.

Why smallpox was Why smallpox was an ideal candidate for eradication an ideal candidate for eradication

(as Jenner recognized)(as Jenner recognized) Humans were the only repositoryHumans were the only repository Immunity easily acquired through vaccinationImmunity easily acquired through vaccination

—and persisted longer than thought—and persisted longer than thought Heat-stable vaccine suitable for any climateHeat-stable vaccine suitable for any climate Highly efficient, low cost mass vaccination Highly efficient, low cost mass vaccination

device device Surveillance was effective: the disease was Surveillance was effective: the disease was

easily recognized easily recognized Rings of containment prevented spread Rings of containment prevented spread

Case of New York City, 1947Case of New York City, 1947

1 index case led to 12 additional ill, 2 deaths 1 index case led to 12 additional ill, 2 deaths Disease not recognized until 2 patients in the Disease not recognized until 2 patients in the

hospital contracted the diseasehospital contracted the disease 24-hour vaccination service; 2 million 24-hour vaccination service; 2 million

vaccinated in first two weeks; vaccinated in first two weeks; 6.3 million vaccinated in a month; 8 deaths 6.3 million vaccinated in a month; 8 deaths

from the vaccinefrom the vaccine Had the vaccination program been delayed by Had the vaccination program been delayed by

1 week, >4,000 cases, with perhaps 900 deaths1 week, >4,000 cases, with perhaps 900 deaths

Why rings of containment accompanied by mass Why rings of containment accompanied by mass vaccination work:vaccination work:

Smallpox is slow to develop (12Smallpox is slow to develop (12thth day) day)vaccination ‘takes’ quickly (by 9vaccination ‘takes’ quickly (by 9thth day) day)

Rings of containment, encircle every Rings of containment, encircle every outbreak: vaccinate and quarantineoutbreak: vaccinate and quarantine

Eradication certified: Dec. 9, 1979Eradication certified: Dec. 9, 1979

Global eradication of smallpox: Global eradication of smallpox: a victory of the Cold Wara victory of the Cold War

Smallpox vaccination “has averted more Smallpox vaccination “has averted more human suffering and saved more lives than any human suffering and saved more lives than any other single medical intervention.”other single medical intervention.”

““Had smallpox not been eradicated, in the past Had smallpox not been eradicated, in the past twenty years, 350 million new victims, and an twenty years, 350 million new victims, and an estimated 40 million deaths”estimated 40 million deaths”

Eradication required the mobilization of Eradication required the mobilization of existing health structures in countries around existing health structures in countries around the world the world

New candidates for eradication New candidates for eradication (World Health Organization)(World Health Organization)

Polio, victory when? Polio, victory when? begun 1988 (Rotary International raised ¼ billion$ in two begun 1988 (Rotary International raised ¼ billion$ in two

years) years) incidence has shrunk 99% to fewer than 500 cases worldwide incidence has shrunk 99% to fewer than 500 cases worldwide

in 2003in 2003 In 2003, wild polio-virus remains in only 6 countries: In 2003, wild polio-virus remains in only 6 countries:

Afghanistan, Egypt, India, Niger, Nigeria and PakistanAfghanistan, Egypt, India, Niger, Nigeria and Pakistan. . 2004 spread from Nigeria to Mecca and beyond2004 spread from Nigeria to Mecca and beyond

Leprosy: Using multi-drug therapy reduced number of Leprosy: Using multi-drug therapy reduced number of cases from 12 million in the 1980s to less than 1 million cases from 12 million in the 1980s to less than 1 million in 2000in 2000

Smallpox Smallpox and Bioterrorismand Bioterrorism

Use of smallpox as a weapon, Use of smallpox as a weapon, 1763-17751763-1775

Used by British against Indians in the French-Used by British against Indians in the French-Indian war (1763): “…we gave them two Indian war (1763): “…we gave them two blankets and a handkerchief out of the blankets and a handkerchief out of the Smallpox Hospital”Smallpox Hospital”

Battle of Quebec, 1775: Smallpox defeated the Battle of Quebec, 1775: Smallpox defeated the rebel American army. rebel American army.

British against American rebels (1778): British against American rebels (1778): “Dip arrows in matter of smallpox and twang “Dip arrows in matter of smallpox and twang them at the American rebels…”them at the American rebels…”

Smallpox: Smallpox: bioterrorist threat is real, bioterrorist threat is real,

but is it exaggerated?but is it exaggerated? Smallpox is highly contagious—but Smallpox is highly contagious—but

Some residual immunity may remain Some residual immunity may remain Vaccination stocks are substantial, sufficient for Vaccination stocks are substantial, sufficient for

entire US populationentire US population What is the risk of an outbreak? Not a medical What is the risk of an outbreak? Not a medical

question. question. Mortality (30%) is exaggerated—high figures Mortality (30%) is exaggerated—high figures

are for small populations (Boston, 1721, 14%)are for small populations (Boston, 1721, 14%) Risk of vaccination complications may out-weigh Risk of vaccination complications may out-weigh

benefits—until an outbreak is confirmed benefits—until an outbreak is confirmed

Dangers of smallpox as a weaponDangers of smallpox as a weapon

Virus can be manufactured, stored and made into an Virus can be manufactured, stored and made into an aerosol.aerosol.

Once released, contagion would spread through non-Once released, contagion would spread through non-immune population.immune population.

HoweverHowever Extremely difficult to obtain stocks and to Extremely difficult to obtain stocks and to

manufacture.manufacture. Not as contagious as measles or flu—and substantial Not as contagious as measles or flu—and substantial

residual immunity remains among older adults.residual immunity remains among older adults. Virus spread is “slow moving” (Rand Study, 2002)Virus spread is “slow moving” (Rand Study, 2002)

Why vaccinating lots of people is not Why vaccinating lots of people is not a good idea: risk are high and rings a good idea: risk are high and rings

of containment effective of containment effective

Vaccinating every AmericanVaccinating every American400 deaths.400 deaths. Particularly risky for those with Particularly risky for those with

immunodeficiency and infants (<2 years)immunodeficiency and infants (<2 years) New vaccine may have lower riskNew vaccine may have lower risk Residual immunity among older adults, Residual immunity among older adults,

vaccinated 30 or more years agovaccinated 30 or more years ago Recently vaccinated “can transmit the vaccinia Recently vaccinated “can transmit the vaccinia

virus to patients in the hospital setting, where it virus to patients in the hospital setting, where it is fatal in as many as 11 percent of cases”is fatal in as many as 11 percent of cases”

From the From the New England Journal of New England Journal of Medicine, Jan 30, 2003,Medicine, Jan 30, 2003,

a contrarian view: Thomas Macka contrarian view: Thomas Mack

Vaccinate 15,000 essential epidemiological personnel Vaccinate 15,000 essential epidemiological personnel (not 10.5 million as proposed by the President(not 10.5 million as proposed by the President30 30 deaths)deaths)

In the unlikely event of an introduction, number of In the unlikely event of an introduction, number of cases could be contained and deaths limited to “10”. cases could be contained and deaths limited to “10”.

Even then, mass vaccination is not justified because Even then, mass vaccination is not justified because the number of deaths from vaccine will be greater the number of deaths from vaccine will be greater than from smallpoxthan from smallpox

Be prepared, but wait until the first case is identifiedBe prepared, but wait until the first case is identified

Should remaining stocks be Should remaining stocks be destroyed?destroyed?

Destruction of remaining stocks Destruction of remaining stocks of smallpox: principal opponent: of smallpox: principal opponent:

US Defense DepartmentUS Defense DepartmentPro destructionPro destruction

An unnecessary risk: An unnecessary risk: little benefit from maintaining stockslittle benefit from maintaining stocks

Take the moral high-groundTake the moral high-ground

ConCon Stocks may be used to develop a “cure”Stocks may be used to develop a “cure” May be useful in developing new vaccinesMay be useful in developing new vaccines