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Cynthia Morgan, PhD, RN Pandemic Influenza Coordinator Texas Department of State Health Services. Preparing for pandemic influenza. Khao Beach 12/5/2004. Thailand Tsunami. Disasters vs. Pandemics. Limited in scope to a certain area Limited in time from minutes to days Visible evidence
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Cynthia Morgan, PhD, RN Pandemic Influenza Coordinator Texas Department of State Health Services Preparing for pandemic influenza
Khao Beach 12/5/2004 ThailandTsunami
Disasters vs. Pandemics • Limited in scope to a certain area • Limited in time from minutes to days • Visible evidence • Material casualties predominate • Can count on local material aid and state/federal response • Localized economic impact • Widespread geographic impact • Occur in 6w to 2m waves over ~one year • Invisible evidence • Human casualties predominate • State/federal response may be very limited • Widespread economic crisis
Seasonal Annually 1 Wave Known virus Vaccine available (usually) High mortality young & old esp. w/ health problems Pandemic Irregular intervals >1 wave Novel virus No or mismatched vaccine High mortality in 20-50 year olds; mortality in young similar to seasonal flu Seasonal vs Pandemic Flu
The Avian H5N1 Flu Threat to Humans • H5N1 rapid spread in Asia now considered endemic • Spreading across Europe and Africa • Severe disease in humans – high deaths in 15-50 year old age groups • Potential exposure in Asia & Africa ongoing – free range chickens for income and food • Recent genetic sequencing – 2 mutations which may make H5N1 more adaptable to humans
Difference between avian & pandemic infuenza • Avian influenza is a disease of birds that humans acquire by very close contact • Pandemic flu is the strain that infects people and is easily transmitted between people
Government/public health pandemic flu planning goals • Limit illness and death arising from infection. • Provide treatment and care for those who become ill. • Minimize disruption to health and other essential services. • Maintain business continuity as far as possible. • Reduce as far as possible disruption to society.
Potential pandemic interventions Social Distancing Antivirals Illness Post-exposure prophylaxis Vaccine
Social distancing – first line of defense • Can be instituted immediately in any setting • Does not require licensed professionals to initiate • Supplies are inexpensive, easily stored • Have demonstrated effectiveness • When used with pharmacological interventions, significantly improves outcomes
Community social distancing strategies Restriction of movement Isolation and treatment of ill persons Voluntary home quarantine and post exposure prophylaxis of contacts Curfew Closure of public places Cancellation of public events Dismissal of students from school Business closures
#1 Pandemic outbreak: No intervention #2 Daily Cases Pandemic outbreak: With intervention #3 Days since First Case Community-Based Interventions 1. Delay disease transmission and outbreak peak 2. Decompress peak burden on healthcare infrastructure 3. Diminish overall cases and health impacts 11
Who infects who? School Household Workplace Children/Teenagers 29% Adults 59% Seniors 12% Likely sites of transmission Demographics Glass, RJ, et al. (2005) Local mitigation strategies for pandemic influenza. NISAC, SAND Number: 2005-7955J Glass, RJ, et al. (2006). Targeted social distancing design for pandemic influenza.. Emerging Infectious Diseases, 12. 11.
Value of combining strategies – Longini Model
The importance of timing Too early • Economic & social hardship w/o PH benefit • Compliance fatigue Too late • Extensive spread w/o PH benefit Just right • Maximum benefits / minimal loss
Just right . . . • early enough to preclude the initial steep upslope in case numbers • long enough to cover the peak of the anticipated epidemic curve • limits intervention fatigue
Assumptions related to pharmaceutical interventions • Current societal expectations about access to health care will have to change in light of a public health crisis of major proportions. • Demand for significant resources will be regional, and treatment and prevention strategies will be tailored to unique state, regional, and local circumstances
More assumptions • If resources and supplies are present in inadequate amounts, distrbution will be prioritized based on epidemiology and response • Employers, healthcare partners, and local/state government will identify in advance those serving in essential response functions.
Differences between antibiotics and antivirals • Kills or inhibit the growth of micro-organisms • Inhibit the reproductive cycle of viruses Antibiotics Antivirals • Shorten duration • Shorten duration • Prevent later disease stage development • Shorten illness 1-2 days Cure disease Does not “cure” disease • Prevent disease • Resistance may develop • Prevent disease • Resistance may develop
Role of Antivirals • At best, antivirals are a stop gap measure until a vaccine is available • Antivirals must be used with social distancing interventions
Even more assumptions • DSHS assumes manufacturers and distributors will provide adequate amount of antivirals to the private sector • Those insured will obtain medications in usual ways • Hospitals will bear responsibility for their own workers
Source of Antivirals: "DSHS cache" • Carry-forward dollars from the Public Health Preparedness Co-Agreement • 165,582 courses purchased • 16,000 courses to each Health Service Region • 21,582 courses at central office • Not covered under SLEP; Shelf life just extended to 7 years.
"General Revenue Cache" • Federal Contract subsidized / unsubsidized • 2.3 M courses available to purchase @ 75 / 25% cost sharing • Legislature allocated $10M GR funds bought 676,774 courses • Purchase offered to state agencies and organizations involved in response efforts • Long term storage requirement • State - purchased antivirals do not qualify for SLEP
“SNS Cache” • Strategic National Stockpile (SNS) • When fully stocked, 3.3 M courses allocated to Texas • Antivirals will be forward-placed when CDC determines the pandemic is “imminent” and Phase 4 declared • No definition of “imminent” • Will be stored centrally • While in the SNS, covered under the SLEP • Storage may be weeks to months
0 3 1 ? 4 2 4 6
Mix of Antiviral Strategies for publicly purchased antivirals Outbreak management • Case and contacts of case • Public health workers involved in outbreak management • Post - Exposure Prophylaxis • Critical service providers • Critical infrastructure employees Treatment • back-up source for short supplies
Supplying publicly purchased antivirals • Outbreak management • Deliver at points of distribution sites for responders • Supplies must be accessible to those involved in investigation and control • Supplies must be available to those being treated or prophylaxed
Supplying Antivirals Issues Pre-exposure Prophylaxis – Tamiflu and Relenza are not part of the CDC or DSHS recommendations • Expensive off contract • Supply issue Delivering antivirals to sick and contacts during outbreak control • If household in isolation and quarantine how will antivirals be obtained? Post-exposure Prophylaxis • Are antivirals necessary for direct care providers when PPE is used?
Supplying Antivirals Strategies • Treatment - Delivery site will be the point of care • Hospitals will be a critical delivery node • Through occupational health for employees • At admission for seriously ill patients • In Emergency Department for high-risk outpatients • Delivery sites for other groups • Outpatient offices and clinics • “Flu clinics” • Pharmacies
Target Groups for Antiviral Drug Interventions Priority groups are defined in the draft DSHSAntiviral Allocation, Distribution, and Storage (AADS) Plan Guidelines • Priorities based on pandemic response goals • DSHS priorities differ from CDC’s DSHS priority groups based on 2 expert panels in Austin and 1 independent one in Amarillo • Ethicists, attorneys, physicians, scientists, professional organizations, faith based organizations, community service organizations • Consensus reached
Potential Target Groups in Texas for Antiviral Drugs and Population Size
Federal Government Strategy for Vaccine Development Examine effects of currently available vaccine technology on H5N1 Accelerate development of cell-based technology Develop dose-sparing strategies, especially adjuvants Develop live attenuated vaccines Develop novel approaches to vaccine development
VaccinesSince 1950s: Egg based technology Depends on fertilized eggs and chick embryos to grow the virus Shortages often due to problems here Requires 4-6 months for vaccine production
Alternatives to Eggs: Cell Culture • Still uses live virus however it grows in media rather than chick embryos • Requires less room • More dependable • Shortens time for vaccine production ~2 months
What is available now? • Egg based (until ~ 2010) • H5N1 avian vaccine requires 90 µg of antigen given in 2 doses • Seasonal vaccine requires 15 µg • Federal government stockpiling 20M 2-dose courses
Improving Effectiveness of Methods: Adjuvants • Agents which modify the effect of other agents • Have few if any direct effects when given by themselves • Used in various pharmaceuticals including cancer chemotherapy • Act by stimulating the immune system
VADS Planning Guidelines • Examines alocation, distribution, and storage for vaccines • Contains priority groups for vaccine • Outlines responsibilities of DSHS, Health Service Regions, and Local Health Departments • Significantly different than AADS since no vaccine will be available through the private sector
Personal preparedness • Why will you need to prepare? • What might you arrange? • What might you purchase? • What are some barriers?
Helpful websites • http://www.pandemicflu.gov/plan/tab3.html • http://www.pandemicpractices.org/files/187/187_handbook.pdf • http://www.pandemicpractices.org/files/234/234_toolkit.pdf • http://www.dshs.state.tx.us/preparedness/Publlic_Guide.pdf
Helpful websites • http://www.pandemicflu.gov/plan/tab3.html • http://www.pandemicpractices.org/files/187/187_handbook.pdf • http://www.pandemicpractices.org/files/234/234_toolkit.pdf • http://www.dshs.state.tx.us/preparedness/Publlic_Guide.pdf
Helpful websites http://www.cdc.gov/business http://www.ready.gov/business/_downloads/pandemic_influenza.pdf http://www.fema.gov/government/coop/ http://www.dshs.state.tx.us/comprep/pandemic/default.shtm