FDA Regulation of Biologics
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Transcript FDA Regulation of Biologics
Why Smallpox Bioterrorism?
Stable aerosol Virus
Easy to Produce
Infectious at low doses
Human to human
transmission
10 to 12 day incubation
period
High mortality rate (30%)
CDC Materials
•Small Pox Vaccine History
1000 AD - China, deliberate inoculation of smallpox
into skin or nares resulting in less severe smallpox
infection. Vaccinees could still transmit smallpox
1796 - Edward Jenner demonstrated that skin
inoculation of cowpox virus provided protection
against smallpox infection
1805 - Italy, first use of smallpox vaccine
manufactured on calf flank
1864 - Widespread recognition of utility of calf
flank smallpox vaccine
1940’s - Development of commercial process
for freeze-dried vaccine production (Collier)
Herd Immunity
Smallpox Spreads to the Non-immune
Immunization Slows the Spread
Dramatically
Epidemics Die Out Naturally
Herd Immunity Protects the
Unimmunized
Smallpox Vaccine
Live Virus Vaccine (Vaccinia Virus)
Crude Preparation We Have Now
Not Cowpox, Might be Extinct Horsepox
Must be Infected to be Immune
Prepared from the skin of infected calves
Filtered, Cleaned (some), and Freeze-dried
New Vaccine is Clean, but still Live
Complications of Vaccination
Local Lesion
Progressive
(Disseminated)
Vaccina
Can be Spread on the
Body and to Others
Deadly Like Smallpox,
but Less Contagious
Encephalitis
Heart Disease?
Historic Probability of Injury
Small Risk from Bacterial and Viral
Contaminants
Small Risk of Allergic Reaction
35 Years Ago
5.6M New and 8.6M Revaccinations a Year
9 deaths, 12 encephalitis/30-40% permanent
Death or Severe Permanent Injury 1/1,000,000
Mostly among immunsupressed persons
Global Eradication Program
1950 - Pan American Sanitary Organization
initiated hemisphere-wide eradication
program
1967 - Following USSR proposal (1958) WHO
initiated Global Eradication Program
Based on Ring Immunization
Vaccinate All Contacts and their Contacts
Isolate Contacts for Incubation Period
Involuntary - Ignore Revisionist History
1977 - Oct. 26, 1977 last known naturally
occurring smallpox case recorded in Somalia
1980 - WHO announced world-wide eradication
Eradication Ended
Vaccinations
Cost Benefit Analysis
Vaccine was Very Cheap
Program Administration was Expensive
Risks of Vaccine Were Seen as
Outweighing Benefits
Stopped in the 1970s
Immunity Declines with Time
Universal Vulnerability
Agriculture and Smallpox
Isolated Communities
Stays Endemic or Dies Out Forever
Most Communities had Significant
Immunity
Synchronous Infection
Break Down of Social Order
Now the Whole World is Susceptible
How Have Risks Changed?
Immunosuppressed Persons Cannot
Fight the Virus and Develop Progressive
Vaccinia
Immunosuppression Was Rare in 1970
Immunosuppression is More Common
HIV, Cancer Chemotherapy, Arthritis Drugs,
Organ Transplants
Role of Medical Care
Smallpox
Can Reduce Mortality with Medical Care
Huge Risk of Spreading Infection to Others
Very Sick Patients - Lots of Resources
Cannot Treat Mass Casualties
Vaccinia
VIG - more will have to be made
Less sick patients - longer time
Complications Last time - 1947
New York Outbreak
Case from Mexico
6,300,000 Vaccinated in a Month
3 Deaths from the Smallpox
6 Deaths from the Vaccine
Would Have Been Much Higher Without
Vaccination?
What would happen now?
Assume 1,000,000 Vaccinated in Mass
Campaign with No Screening
Assume 1.0% Immunosuppressed
10,000 Immunosuppressed Persons
Probably Low, Could be 2%+
Potentially 1-2,000+ Deaths and More
With Severe Illness