Summary of June 15-16, 2005 Meeting of

Joint ACIP/NVAC Working Group on Pandemic Influenza

Vaccine PrioritizationCo-chairs Ban Allos and Gary Freed

NVAC and ACIP Joint MeetingWashington, D.C.

July 19, 2005

Goals of Working Group Meeting

Review information on pandemic influenza impact

Develop draft list of groups for prioritized for pandemic influenza vaccine and presentation to ACIP and NVACConsider sub-prioritization

Timeline and Process April 20, 2005 1st working group meeting Inter-meeting working groups

Prior pandemics Healthcare workers Essential Services Ethics

June 15-16 2nd working group meeting June 22 – conference call with NVAC Pandemic Influenza

Working Group June 30

Presentation to ACIP and sent to NVAC Comments received through July 11

Overall Goals for Pandemic Planning

To minimize hospitalizations and deaths

To preserve critical infrastructure and minimize social disruption

Overall, vaccine and antiviral working groups felt goals should be rank ordered Acknowledged that both goals tightly linked

Overall Goals for Pandemic Influenza Vaccination Program

To vaccinate all persons in U.S. who desire vaccination

In the likely event of a shortage given current vaccine manufacturing capacity, prioritize vaccine: To minimize hospitalizations and deaths To preserve critical infrastructure and minimize social

disruption

Key Assumptions I Health impact of a pandemic

25-30% (range in working age 20-30% most likely) of persons may become ill in major wave

Outbreak period in a community 6-8 weeks per wave with possibly >1 wave in a community

Rates of influenza-related hospitalizations and deaths may vary substantially based on 1918, 1957, and1968 pandemics depending on age and risk group

0.01%-8% persons may be hospitalized 0.001–1% ill persons may die

Medical care services severely taxed or overwhelmed

Key Assumptions II

Health impact of a pandemic Illness duration preventing work for uncomplicated

case influenza: 5 days10% or more workers out of work at the peak of a

major wave Includes work loss caring for self or for ill family member

Assumes 8 week outbreak period and 25% overall attack rate

Key Assumptions III Vaccine production and use

Time from candidate vaccine strain to first doses >6 months Current optimistic U.S. production capacity for inactivated vaccine

5 M doses per week Current capacity for live attenuated vaccine production 1.5 million

doses per week Bulk material made in the U.K., not in U.S.

2 doses per person likely needed for immune response Dept of Defense high priority for vaccination 0.5 M-1.5 M persons

Limited supply antiviral medications Thus, need for rationale, explicit prioritization of vaccine However, any prioritization scheme will likely require

modification based on epidemiology of a new pandemic

Key Assumptions IV Critical Infrastructure

Considered groups or subgroups who Direct role in reducing hospitalizations and deaths Role in preventing social disruption Likely to experience increased demand during pandemic

Little information available to assess potential impact of pandemic influenza on non-healthcare and non-military sectors

Information from prior pandemics difficult to apply now due to changes in business practices

More work with CI groups need to identify groups and sub-groups most in need of vaccination and/or antivirals

Main Vaccine Prioritization Considerations Impact of past pandemics (and inter-pandemic

influenza) by age and risk group on hospitalization and death

Likelihood of response to vaccination Directness of role in preventing hospitalizations

and deaths and preventing social disruption Current U.S. inactivated vaccine manufacturing

capacity Lessons learned from 2004-05 influenza vaccine

shortage

0153045607590

105120135150165180195210225240

1 2 3 4 5 6 7 8 9 10 11 12Months of inactivated influenza

vaccine production

1 dose

2 full doses

Pandemic vaccination program progress toward meeting 80% goal for target groups, assuming 5 million

doses per week

(HR 88.3M; ~HCW 9M; ~CI 8.9M; children 5-17 yr 53.2M; children 6m-17yr 69.3M)

No. doses for immunity

Va

ccin

ate

d P

op

ula

tio

n

(cu

mu

lati

ve m

illio

ns)

High Risk Only

HCW Only

Pandemic begins ????

High Risk + HCW

Critical Infrastructure Only

Draft Key Conclusions

“Maximize preparedness to minimize allocation needs”, Kathy Kinlaw

In order to reduce need for rationing, working group strongly expressed that investment needed to: Expand U.S. vaccine manufacturing capacity Conduct research to

Extend existing vaccine supply Improve efficiency in vaccine production Develop new vaccines with improved effectiveness and ease of

manufacturing Develop and test seed lots vaccine with pandemic potential Improve interpandemic vaccine delivery infrastructure, e.g. adult

vaccination program Consider stockpiling monovalent vaccine strain(s) with greatest

pandemic potential

Other Draft Key Conclusions II Initiate and plan for use of LAIV along with inactivated

vaccine Concurrent with efforts to minimize vaccine shortfalls, further

enhance antiviral medication stockpile Given range of impact of pandemics, revisit recommendations

on regular basis before and during a pandemic Revise as appropriate

Reserve some vaccine for vaccination of workers critical to response to unforeseen emergencies

Obtain public input on vaccine prioritization Develop pre-pandemic public & providers communication

tools

Draft Priority Groups Personnel Cumulative

Element and Tier ( 1,000’s) total (1,000’s)1A. Health care involved in direct patient 9,000 9,000 contact + essential supportVaccine and antivirals manufacturing 40 9,040 personnel

1B. Highest risk group 25,840 34,880

1C. Household contacts children <6 months and 10,700 45,580Severely immune compromised, and pregnant women

1D. Key government leaders +critical public 151 45,731 health pandemic responders

2. Rest of high risk 59,100 104,831

Most CI and other PH emergency responders 8,500 113,331

3. Other key government health decision 500 113,831 makers + mortuary services

4. Healthy 2-64 years not in other groups 179,260 293,091

Definitions

1A. Healthcare workers - those with direct patient contact plus critical healthcare support staff Includes inpatient, outpatient, home care,

EMS, blood collection, supporting laboratories, vaccinators and public health providers with direct patient contact plus their critical support personnel

Definitions

1B. Highest risk group >64 with 1+ high risk conditions 6m-64y with 2+ high risk conditions Hospitalization in prior year with pneumonia or

influenza or an ACIP high risk condition 1C. Household contacts of children <6m or

severely immune compromised 1C. Pregnant women in any stage of pregnancy 1D. Key government leaders and critical

pandemic public health responders

Definitions

2. Other high risk

>65 years with no high risk conditions 6 months-64 years with 1 high risk condition 6-23 month olds

Critical infrastructure groups Other public health emergency responders Public safety (fire, police, 911 dispatchers, correctional facility staff) Utility workers essential for maintaining functional of power, water,

and sewage systems Transportation workers critical for transportation fuel, food, water,

and medical supplies and for public ground transportation Telecommunications/IT personnel essential for maintaining

functional communication and network operations

Definitions

3.Other key government health care decision

makers Mortuary services

4. Healthy persons 2-64 years not included in above categories

Other Opinions on Tiering No subtiering – keep as simple as possible Collapse groups 1C and 1D since 1D group small Move key government leaders to tier 1A Move critical public health responders to tier 1A Subtier group 2 into groups (2A and 2B), putting high risk patients first then

CI groups Combine tier 3 with tier 2b Delete tier 3

Differences with Canadian pandemic plan tiering May require re-ordering if severe illness rates in 20-40 yo = <1 yo = >64 yo

Canadian Pandemic PlanPriority Groups Applicable Category

Group 1

Health care workers, paramedics/ambulance attendants and public health workers

Front-line Health Care Provider

Essential Health Care Provider

Public Health Responder

Essential Health Support Services

Key Health Decision Maker

Group 2 Essential service providersPandemic Societal Responder

Key Societal Decision Makers

Group 3Persons at high risk of fatal

outcomes

A. Nursing home residentsB. Any age with high risk conditionsC. Healthy >65 yearsD. 6-23 monthsE. Pregnant women

Group 4 Healthy adults N/A

Group 5 Healthy children 2-18 yrs N/A

Groups for whom antiviral strategy may be considered Nursing homes with 24-hour skilled nursing care

Rationale Less likely to mount a protective immune response compared with other high

risk groups Semi-closed populations with medical director Vaccination of healthcare workers and critical support staff would be high

priority Need for prioritization in setting of severe vaccine shortage and severe

impact in overall U.S. population Draft recommendation

High vaccination rates of staff Limit ill staff and visitors Close monitoring for respiratory outbreaks Aggressive use of antivirals among nursing home residents for outbreak

control

Antiviral strategy, continued

Severely immune compromised persons who are not likely to respond to vaccination Rationale

Persons severely immune compromised unlikely to develop protective immune response (e.g. children with SCID, recent BMT, etc.)

Recommendation High vaccination rates of healthcare workers who work closely with

these groups Vaccination of household contacts Close monitoring for respiratory illness Aggressive use of antivirals for treatment of severely immune

compromised Consider antiviral prophylaxis

Summary

Strong consensus for strengthening vaccine supply in inter-pandemic period to minimize need for prioritization

If prioritization needed Healthcare workers Highest risk who can be vaccinated Household contacts of highest risk who won’t respond to vaccine Rest of high risk and most critical infrastructure Rest of persons 2-64 years

Prioritization will need to be updated as additional information is known

Thank you to the working group participants and coordinators

Draft Priority Groups Personnel CumulativeElement and Tier ( 1,000’s) total (1,000’s)1A. Health care involved in direct patient 9,000 9,000 contact + essential supportVaccine and antivirals manufacturing 40 9,040 personnel

1B. Highest risk group 25,840 34,880

1C. Household contacts children <6 months and 10,700 45,580Severely immune compromised, and pregnant women

1D. Key government leaders +critical public 151 45,731 health pandemic responders

2. Rest of high risk 59,100 104,831

Most CI and other PH emergency responders 8,500 113,331

3. Other key government health decision 500 113,831 makers + mortuary services

4. Healthy 2-64 years not in other groups 179,260 293,091

Other Opinions on Tiering

No subtiering – keep as simple as possible Collapse groups 1C and 1D since 1D group small Move key government leaders to tier 1A Move critical public health responders to tier 1A Subtier group 2 into groups 2A and 2B, putting high risk

patients first then CI groups Combine tier 3 with tier 2b Delete tier 3

Canadian Pandemic PlanPriority Groups Applicable Category

Group 1

Health care workers, paramedics/ambulance attendants and public health workers

Front-line Health Care Provider

Essential Health Care Provider

Public Health Responder

Essential Health Support Services

Key Health Decision Maker

Group 2 Essential service providersPandemic Societal Responder

Key Societal Decision Makers

Group 3Persons at high risk of fatal outcomes

A. Nursing home residentsB. Any age with high risk conditionsC. Healthy >65 yearsD. 6-23 monthsE. Pregnant women

Group 4 Healthy adults N/A

Group 5 Healthy children 2-18 yrs N/A

Deaths per 100,000 in selected age groups

<1 yr 25-44 yr >64 yr

1918 1000 700 410

1957 250 15 250

1968 210 6 *240

<1 yr 25-44 yr >64 yr

HR 1968 *NA 185 736

non-HR 1968

29 241

HR Inter-pandemic

**NA 230 ***460-2810

Non-HR IP

40 60-660

*0-4 yrs 1900 for HR, 530 non-HR**<6 months olds 900***Up to 8600 for elderly with both heart andlung disease

Hospitalizations per 100,000 in selected age groups

*Death rate as high as 870 in very high risk group, e.g. elderly with both lung and heart disease

Estimate of Days Lost From Work Due to Illness in Self or FamilyXinzhi Zhang, MD PhD and Martin I. Meltzer, PhD MS

Modeled lost work days from illness using FluAid and FluSurge and 2000 Census

Inputs: Days lost from work due to illness

by different triage (death, hospitalization, outpatient, self-cured) and age group

Days lost from work due to caring for family member by different triage and age group

Other assumptions employment rate, marriage rate, work days per month

Assumed outbreak period 8 weeks and 25% influenza illness rate as base-case

Model Inputs and Total Lost Days

ScenarioSelf-care

Outpatient Hosp. DeathSelf-care

Outpatient Hosp. Death

A 1 3 7 40 1 3 7 10

B 5 7 12 40 3 5 10 12

Days of work for own illness Days caring for others

Work Days Lost Scenario A Scenario B

Most Likely 130,672,484 269,845,189

Minimum 110,435,229 249,341,669

Maximum 161,643,371 300,682,747

Proportion of work day loss due to pandemic influenza, 8 week outbreak, 25% attack rate (most likely)

0%

2%

4%

6%

8%

10%

12%

1 8 15 22 29 36 43 50

Days of outbreak

Scenario B (10%)

Scenario A (4.8%)

Limitations Assumptions of work day loss for caring and illness fall

into a large range Largely unknown from literature For interpandemic influenza, lost work days per illness-like

illness average 1 day in US studies Assumptions of distribution of days lost from work may

not reflect the real situation (e.g. community, enterprise etc.)

Meeting subject matter experts felt that peak would be sharper than in the model, particularly for smaller communities

Reference• Meltzer MI, Cox NJ, Fukuda K. The economic impact of pandemic influenza in the United

States: implications for setting priorities for intervention. Emerg Infect Dis 1999;5:659-71. Available on the Web at: http://www.cdc.gov/ncidod/eid/vol5no5/meltzer.htm

• Meltzer MI, Cox NJ, Fukuda K. Modeling the economic impact of pandemic influenza in the United States: implications for setting priorities for intervention. Background paper; 1999. Available on the Web at: http://www.cdc.gov/ncidod/eid/vol5no5/melt_back.htm

• Meltzer MI, Shoemake H, Kownaski M. FluAid 2.0: a manual to aid state and local-level public health officials plan, prepare, and practice for the next influenza pandemic. Centers for Disease Control and Prevention, U.S. Department of Health and Human Services; 2000.

• Zhang X, Meltzer MI, Wortley P. FluSurge2.0: a manual to assist state and local public health officials and hospital administrators in estimating the impact of an influenza pandemic on hospital surge capacity (Beta test version). Centers for Disease Control and Prevention, U.S. Department of Health and Human Services; 2005.