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Pandemic Flu Planning for Schools
Pandemic Flu Planning Pandemic Flu Planning for Schoolsfor Schools
Eden Wells, MD, MPHEden Wells, MD, MPHMichigan Department of Community HealthMichigan Department of Community Health
Influenza Strains• Type A
– Infects animals and humans– Moderate to severe illness– Potential epidemics/pandemics
• Type B– Infects humans only– Milder epidemics– Larger proportion of children affected
• Type C– No epidemics– Rare in humans
Source: CDC
A’s and B’s, H’s and N’s
• Classified by its RNA core– Type A or Type B influenza
• Further classified by surface protein– Neuraminidase (N) – 9 subtypes known– Hemagluttin (H) – 16 subtypes known
• Only Influenza A has pandemic potential
Influenza Virus Structure
A/Moscow/21/99 (H3N2)
NeuraminidaseHemagglutinin
Type of nuclearmaterial
Virustype
Geographicorigin
Strainnumber
Year of isolation
Virus subtype
Influenza Overview• Orthomyxoviridae, enveloped RNA virus• Strains
– Type A– Type B– Type C
• Further classified by surface protein– Neuraminidase (N) – 9 subtypes known– Hemagglutinin (H) – 16 subtypes known
Source: CDC
Influenza A: Antigenic Drift and Shift• Hemagglutinin (HA) and neuraminadase (NA)
structures can change
• Drift: minor point mutations– associated with seasonal changes/epidemics– subtype remains the same
• Shift: major genetic changes (reassortments)– making a new subtype – can cause pandemic
Seasonal Influenza
• October to April• People should get flu vaccine• Children and elderly most prone• ~36,000 deaths annually in U.S.
Seasonal Effects
Seasonal Influenza Surveillance
Differentiating Influenza
Seasonal– Caused by influenza A or B strains circulating in humans – ~36,000 human deaths annually in USA
Avian– Caused by Influenza A– Shorebirds and water fowl are the reservoir and rarely
see outbreaks, except in current H5N1 strain– Domestic poultry (chickens and turkeys), causes
morbidity and mortality with outbreaks annually worldwide
Pandemic– When new virus strain occurs– Humans lack immunity– Simultaneous epidemics worldwide– Disease easily transmitted between people– Significant number of illness and deaths
Avian InfluenzaThe “Bird Flu”
Images from: http://www.usda.gov/oc/photo
Avian Influenza• Infection can be in two forms
– “low pathogenic” (LPAI) - causes mild illness and may go undetected
– “highly pathogenic” (HPAI) - affects multiple organs, spreads rapidly among birds, causes high mortality very quickly
Avian Influenza A (H5N1)
• Discovered in1997 Hong Kong• Now multiple epizootics worldwide• Has not entered the Western Hemisphere• Has not met WHO Pandemic criteria
– New strain– Causes severe illness in humans– Sustained transmission from person to person
Poultry Outbreakshttp://www.oie.int/eng/en_index.htm (5/17/06)
• Egypt• France• Georgia• Germany• Greece• Hong Kong • Hungary• Kazakhstan • India• Indonesia• Iraq• Iran• Israel• Italy• Thailand• Turkey• Ukraine
• Jordan• Malaysia• Myanmar• Niger• Nigeria• Palestinian• Pakistan• Poland• Romania• Russia• Serbia &
Montenegro• Slovakia• Slovenia• Sudan• Vietnam
• Afghanistan • Albania• Austria• Azerbaijan• Bosnia & Herzegovina• Bulgaria• Burkina Faso • Cambodia• Cameroon• China • Côte d'Ivoire • Croatia• Czech Republic • Denmark• Sweden• Switzerland• United Kingdom
The Role of Animals in Influenza A Infection
Shore Birds and Wild Waterfowl
Domestic BirdsMammals
Humans
Domestic Poultry Surveillance
• Michigan veterinarians are responsible for overall livestock and poultry reportable disease programs
• They conduct investigations into reports of diseases such as:
– Avian influenza– Rabies– Eastern equine encephalitis– Equine infectious anemia– Tuberculosis– Psittacosis
www.michigan.gov/MDA
• Wildlife biologist monitor diseases of wild birds at the population level
• Sick or Dead Wildlife website reporting
• Bird Banding
• Hunter Surveillance
Wild Bird Surveillance
http://www.michigan.gov/dnr
Humans at Risk• Transmission from birds to humans
does not occur easily– Contact with feces or secretions from
infected birds– Risk with butchering, preparing,
defeathering of infected birds– NOT transmitted through cooked food
(WHO, August 7, 2006)
33%412Turkey67%1624Thailand
63%58Azerbaijan
45%4293Vietnam
100%66Cambodia
0%01Djibouti
78%4254Indonesia100%22Iraq
58%135233Total
43%614Egypt
63%1219China
Case Fatality
DeathsH5N1 Cases
Country
Implications for Human Health
• Asian Strain H5N1 in humans more aggressive than seasonal flu strains– Severe clinical course– Rapid deterioration– High fatality– Low transmissibility human-to-human
• Incubation may be longer than seasonal influenza– Seasonal influenza: 2-3 days– H5N1: possibly up to 10 days
• More studies needed
What is the H5N1 Pandemic Risk?
• Three conditions must be met for a pandemic to start:– Emergence of a new influenza subtype
– The strain infects humans causing serious illness
– Spreads easily between humans
Current U.S. Status
• No current evidence in U.S. of highly pathogenic H5N1 in:– Wild birds– Domestic poultry– Humans
Pandemic Phases (WHO)
Planning for an Impending Pandemic
Planning for an Impending Planning for an Impending PandemicPandemic
The Role of Public HealthThe Role of Public Health
20th Century Influenza Pandemics
• 1918 – 1919, “Spanish Flu” (H1N1)– Influenza A H1N1 viruses still circulate today– US mortality: approx. 500,000+
• 1957-58, “Asian Flu” (H2N2)– Identified in China (February 1957) with spread
to US by June– US mortality: 69,800
• 1968-69, “Hong Kong Flu” (H3N2)– Influenza A H3N2 viruses still circulate today– First detected in Hong Kong (early 1968) and
spread to US later that year– US mortality: 33,800
Estimated Impact of a Future Pandemic in Michigan
(*Michigan figures developed with Flu(*Michigan figures developed with Flu--Aid 2.0 software, CDC)Aid 2.0 software, CDC)
Characteristic Moderate(1957 / ‘68-like)
Severe (1918-like)
Illness 3.4 million 3.4 million
Outpatient 2.5 million 1.5 million
Hospitalization 51,000 420,000
Deaths 15,000 125,000
MDCH Pandemic Influenza Plan 2005
• Revision of 2002 plan• Released November 2005• Appendix to MDCH All-Hazards
Response Plan• Pandemic plan updated as needed• www.michigan.gov/influenza
Public Health Response:Risk Communication
• Intra-agency– Health Alert Network (MI-HAN)
• Inter-agency– AIIWG– MI-HAN
• Stakeholders– Website:
www.michigan.gov/flu– MI-HAN
Influenza Surveillance
• Michigan Disease Surveillance System
• Sentinel Surveillance• Syndromic
– Pharmacy– ER
• Laboratory • National • International
LHD’s/LHD’s/MDSSMDSS
NonNon--MDCH MDCH LabsLabs
WHO DataWHO Data
CDC DataCDC DataLHD’s/LHD’s/
Healthcare Healthcare providersproviders
PharmacyPharmacyOTCOTC
Sentinel Sentinel PhysiciansPhysicians
ER ER SyndromicSyndromic
HospitalsHospitals
MDCH MDCH LabsLabs
MiMi--FluFluFocusFocus
Measures To Combat Pandemic Flu
• Antiviral medications – Oseltamivir (Tamiflu®)or others
• Education to encourage self-diagnosis• Public health information (risk avoidance, advice
on universal hygiene behavior)• Face masks for persons with symptoms• Cancellation of school and social gatherings• Deferring travel to involved areas
Medical Containment (models)
• Targeted antivirals
• Widespread antivirals prophylaxis
• Vaccine stockpiles
• ?”Tiered Layered Containment”
Social Distancing-Possible Measures
• School closures
• Travel restrictions- (models don’t seem to impact overall attack rate)
• Case isolation/ home quarantine
Pandemic PlanningPandemic PlanningPandemic Planning
Michigan Schools and Public Health
Lead for School Response
• United States: Division of Adolescent School Health – CDC
• Michigan: Michigan Departments of Education and Community Health
• School Jurisdiction: Superintendent
• School: Superintendent, Building Principal
Leads for Public Health• International: World Health Organization
• United States: Centers for Disease Control and Prevention, DHHS
• Michigan: Michigan Department of Community Health
• County: Local Health Department/Jurisdiction
Michigan School Communications
• MDE Official Listserv to all superintendents
• Direct connections to professional organizations (MASA, MASB, MAISA, MEA, CSHCA)
• Webstreaming• Media• School Master Database
http://www.emc.cmich.edu/avian/
Infection Controlin Schools
Non-Pharmaceutical Interventions
• Social distancing
• Hand Hygiene
• Respiratory/Cough etiquette
School Administrators• Develop school pandemic plan• Know the local health department• Know the public health authority of
the Local Health Officer• Educate staff, students, and parents• Educate food service workers
Teachers
• Become involved in planning
• Teach students
• Keep updated in public health information
Toolkit for SchoolsFact sheetPresentationVideo on proper hand washingHealth and hygiene lesson plansPostersContact lists
http://www.scrubclub.org/home.php
Avian/Pandemic Influenza Fact Sheet
Public Health/School Pandemic Planning Collaboration-Summary
• A pandemic affects all sectors of society• Schools great sites for public health education• School closure may be a tool to mitigate
pandemic spread• Collaborative pandemic planning enhances all-
hazard responses to ANY emergency• Respiratory etiquette/hand hygiene education
useful any time
Have a Plan• Develop• Exercise• Update• Review• Exercise• Update….
CDC/EOC-PHIL
Health Advice:Good now, Good in a Pandemic
• Get your annual flu shot– It won’t protect you against a pandemic strain but you will
be stronger to fight a new strain if you are healthy
• Stay at home if you have a fever; don’t send kids to school with a fever
• Wash hands with soap or hand sanitizers when you sneeze or cough
• Get adequate sleep, eat healthy, stay hydrated
References
• Local Health Department• Michigan Department of Community
Health (www.michigan.gov/flu)• WHO www.who.int• CDC www.cdc.gov• DHHS (www.pandemicflu.gov)
(CHECKLISTS)