Lessons from Swine Flu Harvey V. Fineberg, M.D. Ph.D. Seasonal & Pandemic Influenza 2006 1 February 2006.

Lessons from Swine Flu

Harvey V. Fineberg, M.D. Ph.D.

Seasonal & Pandemic Influenza 2006

1 February 2006

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US Life Expectancy

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US Life Expectancy

1918 Flu Epidemic

The Great Pandemic of 1918-19

• >20 million deaths worldwide

• >500,000 deaths in the United States

• >200,000 deaths in Great Britain

• >5 million deaths in India

• High mortality among young adults

1918

1976

• American Bicentennial Year

• The most ambitious influenza immunization campaign ever mounted in the U.S. in response to an outbreak of swine flu in Fort Dix, New Jersey

• No influenza epidemic appeared

Sequence of Events in the Swine Flu Affair of 1976

• New flu outbreak – Jan

• CDC decides – Feb-Mar

• HEW endorses, President announces – Mar

• Organization and field trials – Apr-Jun

• Vaccine liability and legislation – Jun-Aug

• Starting and stopping – Oct-Dec

New Flu Outbreak<January>

• Respiratory disease outbreak among army recruits at Fort Dix, New Jersey– Majority are A Victoria influenza– Swine influenza found

• One death • 13 clinical cases• up to 500 with serologic evidence of infection with A Swine

influenza

• No evidence of infection with A Swine influenza at other army camps or elsewhere in New Jersey

US Public Health Mindset about Influenza in 1976

• Relatively severe epidemics tend to occur about once every 11 years

• Antigenic shifts in type A produce severe epidemics

• Predominant H antigens tend to recycle at 60-70 year intervals

• Lesson of 1957 and 1968: too little immunization, too late

• Specter of 1918-1919

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H2 - 68 years

H3 – 68 years

Hsw (H1) - ? years

“Asian”

“Hong Kong”

“Spanish”

Theory of Antigenic Recycling

CDC Decides<February-March>

• Consultations and press conference Feb 19

• ACIP Meetings

• CDC’s Sencer writes “action memorandum”– … “a strong possibility [of] widespread…swine

influenza in 1976-77… population under 50 is almost universally susceptible… ingredients for a pandemic.”

– “The situation is one of ‘go or no go’… A decision must be made now.”

HEW endorses, President announces<March>

• Secretary Mathews to Director of Budget– “There is evidence there will be a major flu

epidemic this coming fall… The projections are that this virus will kill one million Americans in 1976.”

• President Ford convenes a panel of experts at the White House (including Drs. Salk and Sabin) and announces a national immunization program, seeks $135 million appropriation

Organization and Field Trials<April-June>

• Asst Secy for Health Cooper declares goal of 95% immunization in testimony to Congress

• Public opposition surfaces to a pre-committed immunization program– Chief Epidemiologist Goldfield of New Jersey– Editorials in New York Times– Sabin advocates “active stockpiling”

• Field trial shows poor results in children

Where to keep vaccine?

““It would be better to have an immunization It would be better to have an immunization program without an epidemic than an program without an epidemic than an epidemic without an immunization epidemic without an immunization program.” (CDC, 1976)program.” (CDC, 1976)

Vaccine Liability and Legislation<June-August>

• Casualty insurers decline to offer liability coverage to vaccine manufacturers beyond 30 June 1976

• Legionnaire’s disease outbreak in Philadelphia, 1 August 1976

• Legislation adopted making the federal government the defendant in any suit arising from the swine flu program, PL 94-380, 12 August 1976

Starting and Stopping<October-December>

• 1 million persons immunized Oct 1-10

• Three coincident deaths in Pittsburgh Oct 11; President Ford immunized Oct 14

• 40 million vaccinated Oct 1 – Dec 16– Twice as many immunized as in any prior year – Highly variable coverage by city and state

• Guillain-Barré syndrome reported late Nov

• Program suspended on December 16

Seven Critical Features – part 1

1. Overconfidence in theory spun from meager evidence

2. Conviction fueled by pre-existing agendas

3. Zeal by health professionals to make lay superiors “do the right thing”

4. Premature commitment

Seven Critical Features – part 2

5. Failure to address uncertainties

6. Insufficient questioning of implementation prospects

7. Insensitivity to media relations and to long term credibility

Overconfidence in theory spun from meager evidence

• Epidemic appears every 11 years

• Equating severe epidemics with the appearance of new strains

• Recycling antigens every 60 years

Careful historical assessment in the mid-1970’s found…

• The 20 major epidemics between 1729 and 1968 occurred at irregular intervals of between 3 and 28 years (W.I.B. Beveridge, 1977)

• Of the six peak years of excess mortality from Influenza A in the US (1936, 1943, 1953, 1957, 1960, 1963) only one (1957) coincided with an antigenic shift in the virus (W. Dowdle, 1976)

Pre-existing Agendas

• Close the immunity gap (Salk)

• So much to learn (Kilbourne)

• Value of epidemiology (Stallones)

• Importance of prevention (Sencer, Cooper)

• Vital role of the CDC (Sencer)

• Desire to create public-private partnership (Cooper)

Zeal by health professionals

• Concern about political motivation, lack of understanding among lay superiors

• Heroic response to dramatic threat

• Chance to prepare, to make up for the lack of preparedness in Asian Flu epidemic of 1957

Premature Commitment

• Concatenating the decision to begin manufacturing the vaccine with the decision to institute a universal vaccination campaign

• General Accounting Office report to Congress, June 1977: “ …when decisions must be based on very limited scientific data, HEW should establish key points at which the program should be formally reevaluated.”

Failure to address uncertainties

• Failure to estimate risk– Scientists reluctant to quantify subjective risk– Lay leaders do not elicit quantitative estimates

of risk

• Failure to consider threshold conditions during the months of preparation for a change in policy from an immunization program to stockpiling

Insufficient questioning of implementation prospects

• Overstated aims

• Dealing with insurers and manufacturers (liability, profit, purchase guarantees)

• Coping with likely opposition

• Expected delays (liability, dosage, consent)

• Experience in different jurisdictions with past immunization efforts

Insensitivity to media relations and long-term credibility

• Media standards and values– Controversy– Coincident events– Side effects

• Institutional credibility– Professional advisory roles and political

decision making– Short-run and long-run considerations

Five Lessons from Swine Flu

1. Building a base for program review

2. Thinking about doing

3. Thinking of the media

4. Maintaining credibility

5. Thinking twice about medical knowledge

Pitfalls to Avoidin Preparation for Avian Flu

• Confound likelihood and severity

• Fail to scrutinize assumptions

• Overstate goals and objectives

• Fail to communicate and explain

• Over-estimate readiness to implement

Reflections

• Decisions in time and under uncertainty– Low-likelihood, high consequence events– Sequencing, new data, deadlines

• Science and policy interface– Expertise, responsibility, roles

• Public understanding

• Complexity of implementation

• Near and long-term consequences