COCA NPPHI borders communities Pan Flu

Nonpharmaceutical Public Health Interventions:Strategies & Implementation in the Setting of Pandemic InfluenzaLCDR Michael Doney, MD, MPH, MSQuarantine Medical OfficerCenters for Disease Control and PreventionDivision of Global Migration & QuarantineQuarantine & Border Health Services BranchAugust 21, 2006: 

Nonpharmaceutical Public Health Interventions: Strategies & Implementation in the Setting of Pandemic Influenza LCDR Michael Doney, MD, MPH, MS Quarantine Medical Officer Centers for Disease Control and Prevention Division of Global Migration & Quarantine Quarantine & Border Health Services Branch August 21, 2006

Overview of Presentation: 

Overview of Presentation CDC Division of Global Migration & Quarantine CDC Quarantine Stations Nonpharmaceutical Public Health Interventions Proposed Strategies & Implementation Conclusion

CDC Division of Global Migration & Quarantine Mission: 

CDC Division of Global Migration & Quarantine Mission To reduce the morbidity and mortality of immigrants, refugees, travelers, expatriates, and other globally mobile populations, and to prevent the introduction, transmission, and spread of communicable diseases through regulation, science, research, preparedness, and response

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CDC Division of Global Migration & Quarantine

Role and Function of the Quarantine StationsA point of coordination for public health at the port of entry: 

Role and Function of the Quarantine Stations A point of coordination for public health at the port of entry

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VT ME MA NY PA NH WV VA MD NJ RI CT AZ IN WI KY MI OH IA MN MO IL NE KS SD ND AL TN GA SC NC AR LA MS OK Atlanta Chicago Seattle WY ID WA AK OR MT NV UT NM CO East TX Miami FL No.CA So.CA Los Angeles San Francisco CDC Quarantine Stations & Jurisdictions DE HI Honolulu Washington D.C. El Paso Houston Newark New York Boston GU San Juan Minneapolis Detroit Anchorage San Diego West TX PR

Quarantine Station Structure: 

Quarantine Station Structure Officer-in-charge (OIC) Trained public health professional Operational aspects of QS Quarantine Medical Officer (QMO) Physician/Public health practitioner Medical, epidemiologic, & research aspects of QS Quarantine Public Health Officer (QPHO) Trained public health professional Greatest contact with public, airlines, other federal agencies in ports

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If necessary, isolate arriving infected and/or ill persons Assess other passengers or crew who may have been exposed Confiscate, isolate, or quarantine infected or ill animals Confiscate potentially infectious animal products or biological substances Mission of Quarantine Stations To protect the health of the public from communicable diseases through science, partnerships and response at US ports

Quarantinable Conditions and Illnesses of Public Health Importance: 

Quarantinable Conditions and Illnesses of Public Health Importance

Quarantinable Diseases1: 

Quarantinable Diseases1 Historic Cholera Smallpox Yellow fever Plague Diphtheria Most common Infectious TB Recent additions Viral hemorrhagic fevers SARS Pandemic influenza strains 1 As of April 1, 2005

Communicable Diseases of Public Health Importance: 

Communicable Diseases of Public Health Importance Dengue Fever Diarrhea Bacterial Viral Legionellosis Malaria Measles Meningococcal meningitis Mumps Pertussis Polio Rabies Rubella Typhoid Varicella Zoonotic poxviruses

Illness Screening Protocols: 

Illness Screening Protocols

Reporting Responsibilities: 

Reporting Responsibilities 42 CFR 71.21 Radio report of death or illness All conveyances (maritime and air) destined for a US port shall report any death or illness on board to the nearest port prior to arrival

Illness Response: Layers of Surveillance: 

Illness Response: Layers of Surveillance Conveyance or vessel crew Port-based customer service staff Fire, police, paramedics US Customs and Border Protection / US Coast Guard / Immigration and Customs Enforcement / other Federal port-based partners Family members State/local health departments and providers

Identify Ill Passengers: 

Identify Ill Passengers Identify ill passengers with Quarantinable disease Communicable disease of public health importance Specific illness syndromes Public health evaluation Recommendations for travel restrictions/interruptions Limitations: Number of QS staff Limited clinical experience Broad clinical syndromes, not specific diseases

Syndromic Surveillance: 

Syndromic Surveillance Need presumptive diagnosis to act In absence of diagnostic capacity, no specific diagnoses made Group infections by similar symptoms Individual travel and activity history CDC & WHO health alerts Determine probability of “significant” disease

Syndromic Surveillance : 

Syndromic Surveillance Identify & evaluate persons ill upon arrival Defined1 as person with persistent fever (≥100ºF [38ºC]) ≥ 48 hours OR fever with: Rash, Lymphadenopathy, Jaundice, or Diarrhea (with or without fever) Need to add: Fever & cough Fever & symptoms of meningitis/encephalitis 1 Foreign Quarantine Regulations: Title 42 CFR Part 71

Limitations of Syndromic Surveillance: 

Limitations of Syndromic Surveillance Depends on nonmedical persons to identify medical conditions Disincentive to travelers to self-identify Requires clinical manifestation during flight and brief period in the Federal Inspection Services area Biased towards recognition of acute infections (not TB) Common diseases occur commonly

Role of Quarantine Staff in Evaluating Ill Passengers: 

Role of Quarantine Staff in Evaluating Ill Passengers

Illness Response (Passive Surveillance): 

Illness Response (Passive Surveillance) When notified of an illness Quarantine Public Health Officer and/or paramedic meets conveyance or vessel as it arrives All passengers remain seated on board Ill person is evaluated to assess public health risk Others who may assist: Paramedics, Customs and Border Protection officer/US Coast Guard, police department, local health department

Illness Response (Active Surveillance): 

Illness Response (Active Surveillance) Meet each arriving conveyance from countries with disease of interest Ask lead crew member if any illness on board Watch each person disembark; isolate and interview all exhibiting symptoms of illness Utilize toolbox of additional measures May distribute Travel Health Alert Notices Coordinate with state/local health authorities

PARTNERSHIP IS KEY: 

PARTNERSHIP IS KEY The goal of preventing the importation of communicable disease is a team effort and relies on the cooperation of a large network of partners at the port of entry and surrounding community/state.

Nonpharmaceutical Public Health Interventions:Measures and Strategies at Borders and Within Communities to Limit the Spread of Pandemic Influenza: 

Nonpharmaceutical Public Health Interventions: Measures and Strategies at Borders and Within Communities to Limit the Spread of Pandemic Influenza

Definitions: 

Definitions Isolation Separation of ill persons with contagious diseases For ill people Usually in hospital, but can be at home or in a dedicated isolation facility Quarantine Separation or restriction of movement of select person(s) For people exposed but not ill Home, institutional, or other forms (“work quarantine”) Voluntary vs. compulsory

Social Distancing and Infection Control: 

Social Distancing and Infection Control Social distancing (contact interventions) School closure Work closure (telecommuting) Cancellation of public gatherings Infection control (transmission interventions) Face masks Cough etiquette Hand hygiene

Outline: 

Outline The challenge Epidemiology: Breaking the cycle of transmission What is to be done? A strategy for communities

Pandemic Influenza Threat: 

Pandemic Influenza Threat Admiral Benson, CNO, Annual Report to Congress, 1919

Containment Unlikely: 

Failed containment may still delay international spread by 1 month Severe travel restrictions may delay U.S. cases by 1-4 weeks Without intervention, expect international spread in 1 month and U.S. cases in 1 to 2 months. Containment Unlikely

Parameters: 

Parameters Epidemiologic Incubation period Infectious period Mode of transmission Symptoms Age distribution Reproductive rate Intergeneration time Social Mixing patterns Mobility Acceptability of collective actions Acceptability of imposed restrictions Expectations Affordability Resiliency

Potential Tools in Our Toolbox: 

Potential Tools in Our Toolbox Our best countermeasure – vaccine – will probably be unavailable during first wave of pandemic Antiviral treatment may improve outcomes but will have only modest effects on transmission Antiviral prophylaxis may have more substantial effects on reducing transmission Infection control and social distancing should reduce transmission, but strategy requires clarification

Community-Based Interventions: 

Community-Based Interventions 1. Delay disease transmission and outbreak peak 2. Decompress peak burden on healthcare infrastructure 3. Diminish overall cases and health impacts

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Ro = 2 Ro = 1

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2.7 Eubank S, personal communication Effect of Ro on Epidemic Curve

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Weekly mortality data provided by Marc Lipsitch (personal communication)

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Breaking the Cycle of Transmission

Shape of an Epidemic: 

Shape of an Epidemic

Scale-free Networks: 

Scale-free Networks Barabasi AL, Bonabeau E. Scientific American 2003;288:60-69.

Susceptible to Targeted Attack: 

Susceptible to Targeted Attack

Susceptible to Targeted Attack: 

Susceptible to Targeted Attack

Critical Insight: 

Critical Insight Averaging over a highly heterogeneous contact network can hide critical features that could be exploited to design effective mitigation strategies

1918 Age-Specific Attack Rates: 

1918 Age-Specific Attack Rates McLaughlin AJ. Epidemiology and Etiology of Influenza. Boston Medical and Surgical Journal, July 1920.

Who Infects Who?: 

Children/Teenagers 29% Adults 59% Seniors 12% Demographics Glass, RJ, et al. Local mitigation strategies for pandemic influenza. NISAC, SAND Number: 2005-7955J Who Infects Who? School Likely sites of transmission

Social Compartments: 

Social Compartments Workplace Household School

What is to be done? : 

What is to be done?

Targeted Layered Containment:A Strategy for Communities: 

Targeted Layered Containment: A Strategy for Communities

Layered Interventions: 

Layered Interventions ↓ cases ↑ HH & community transmission Close schools HH quarantine ↓ cases ↑ relative importance of workplace & community Social distancing ↓ cases 2.1 1.9 1.9 1.2 1.5 1.5 Keep kids home ↓ HH & community transmission ↑ relative importance of HH & workplace transmission 1.2 0.9

Population-based Containment: 

Population-based Containment Exposure Latent / Infectious Symptomatic / Infectious Susceptible Influenza Asymptomatic / Infectious Quarantine / Isolation Social Distancing Liberal Leave School Closure Infection Control Prophylaxis Infection Control Social Distancing School Closure Targeted Social Distancing Treatment Isolation Shunting

Community Mitigation of Influenza: Information Considered by Mathematical Modelers: 

Community Mitigation of Influenza: Information Considered by Mathematical Modelers Population structure, dynamics, interactions Age groups, social compartments (home, school, workplace) Transmission characteristics of influenza Who infects whom and where? Estimates of transmission among age groups, and % of population in these groups; social compartments Clinical trials of antiviral treatment and contact prophylaxis Impact on transmission

Value of Combining Strategies – Ferguson Model: 

Value of Combining Strategies – Ferguson Model Source: Ferguson N, Nature (online) April 26, 2006

Value of Combining Strategies – Ferguson Model: 

Value of Combining Strategies – Ferguson Model days % of population Source: Ferguson N, Nature (online) April 26, 2006

Value of Combining Strategies –Longini Model: 

Value of Combining Strategies –Longini Model Source: German TC. PNAS (online) April 11, 2006 % of population

Combining strategies – Glass model:Targeted Social Distancing: 

Combining strategies – Glass model: Targeted Social Distancing % of population

Evidence to Support School Closure: 

Evidence to Support School Closure Children are thought to be the main introducers of influenza into households. Children appear to be more susceptible to influenza and more infectious than adults in well-designed prospective studies of risk factors of influenza transmission in households. Nationwide school closure in Israel during an influenza epidemic resulted in significant decreases in the diagnoses of respiratory infections (42%), visits to physicians (28%) and emergency departments (28%), and medication purchases (35%).

What do the Modeling Results Mean?: 

What do the Modeling Results Mean? Not proof of efficacy or effectiveness, BUT offer reason for optimism regarding non-pharmaceutical interventions Suggest that maximal effectiveness will be achieved by appropriate layering and timing Need to be evaluated based upon assumptions and validated against experience

Community Planning for Pandemic Influenza: 

Community Planning for Pandemic Influenza

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No sustained human transmission Sustained human transmission 3 4 5 6 Virus with low pandemic potential Virus with high pandemic potential Rare clusters Small number of cases per cluster Very limited human-to-human transmission Localized Frequent clusters More cases per cluster Common human-to-human transmission Localized Continuous transmission Regular human-to-human transmission Involves general population of large regions (worldwide) Human infections with new subtype No clusters No human-to-human transmission WHO Pandemic Influenza Phase

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No sustained human transmission Sustained human transmission WHO Pandemic Influenza Phase 3 4 5 6 Virus with low pandemic potential Virus with high pandemic potential Imported cases possible Early Late Proposed U.S. Public Health Response in Relationship to WHO Phases Quarantine: No Household Yes Isolation: Individual Social distancing: Individual Community Community

Nonpharmaceutical Interventions: 

Nonpharmaceutical Interventions Depend on virus transmission characteristics and illness severity Measures at borders (international or within countries)- limited early focus, phase 5-6a Travel health alert notices (T-HAN) Entry screening of international travelers Exit screening from affected countries is recommended, especially if most countries not yet affected

Targeted Layered Containment Summary: Nonpharmaceutical Interventions: 

Targeted Layered Containment Summary: Nonpharmaceutical Interventions Ill persons should be isolated (home vs hospital) Voluntary home quarantine for household contacts Social distancing measures School closures may have profound impact Workplace COOP (liberal leave NOT closure) Cancellation of public events? Individual infection control measures Hand washing and cough etiquette for all Mask use for ill persons, PPE stratified by risk Disinfection of environmental surfaces as needed

Factors Affecting Ability of Communities to Implement Nonpharmaceutical Interventions: 

Factors Affecting Ability of Communities to Implement Nonpharmaceutical Interventions Maintenance of critical infrastructure Extent of social cohesion, organization and trust Government stability, political will Communication with remote areas High population densities in cities Financial support, compensation Individuals, businesses, governments

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Additional Considerations Planning for second-order effects Duration of implementation Intervention fatigue Socioeconomic disparities Sustained, predictable absenteeism Economic impact

Questions?: 

Questions?