Steve Cline, DDS, MPH NC Division of Public Health

1. Pandemic Influenza: the “Mother of All Disasters”?October 11, 2007Healthy Carolinians Annual Conference Steve Cline, DDS, MPH NC Division of Public Health

2. Objectives • Review the fundamentals of pandemic influenza • Assess the current threat of pandemic influenza • Review influenza surveillance – How will we know? • Discuss pandemic influenza preparedness and response in North Carolina

3. Influenza A epidemic or pandemic animals and humans differing pathogenicities divided into subtypes based on surface proteins (H & N) 144 combinations constantly mutate variation within subtype Influenza B epidemic humans (primarily) not divided into subtypes Influenza C humans mild respiratory illness Types of Influenza Viruses

4. Seasonal Flu: Signs and Symptoms • Fever • Headache • Muscle aches • Extreme fatigue • Dry cough • Sore throat • Runny or stuffy nose happycarpenter.blogs.com

5. Flu Fundamentals: Respiratory Spread • Transmission: Respiratory droplets • Each infected person infects 2-3 others • Incubation period:1 to 5 days from exposure to onset of symptoms • Communicability: • 1-2 days before symptom onset • 4-5 days after onset • Timing:Peak usually occurs December through March in North America

6. Seasonal Influenza ImpactNC and US Society Deaths 25,000 - 72,000 Hospitalizations 114,000 - 257,500 NC 730 - 2100 NC 3300 - 7500 Physician visits ~ 25 million NC 730,000 Infections and illnesses 50 - 60 million NC 1.7 million Thompson WW et al. JAMA. 2003;289:179-86. Couch RB. Ann Intern Med. 2000;133:992-8. Patriarca PA. JAMA. 1999;282:75-7. ACIP. MMWR. 2004;53(RR06):1-40.

8. Pandemic Influenza • Major mutation occurs • Genetic reassortment of human and avian influenza viruses • Direct animal (poultry) to human transmission • Results in new subtype of influenza A • Avian origin • Adapted to humans • No immunity in the human population • Results in multiple simultaneous epidemics worldwide with enormous numbers of deaths and illness • Six to eight weeks • Multiple waves

9. Pandemics of the 20th Century

11. “Pandemic Watch”

12. Avian Influenza • Water birds are the natural reservoir • Carry virus in intestines • Virus shed in feces and respiratory secretions • Usually do not get sick • Highly contagious among birds • Most of no human health significance

13. Pandemic “Prerequisites” • Novel virus emerges • Novel virus causes disease in humans • Novel virus can be efficiently transmitted person to person Dr. Asamoa-Baah, Assistant Director General, WHO Communicable Diseases

14. WHO Pandemic Phases

16. H5N1 in Humans • Current outbreak began December 2003 • Initially cases were limited to Southeast Asia • Geographic distribution continuing to expand in 2006 • Human cases are now being reported in Europe and Africa

18. Global Migration of H5N1 October 5, 2007

22. Backyard flocks

23. Direct Contact with PoultryPrimary Risk Factor • Plucking and preparing diseased poultry • Handling fighting cocks • Playing with poultry • Consumption of duck’s blood or possibly undercooked poultry

24. “Pandemic Watch”Global Perspective • Good news • No evidence of sustained person-to-person transmission • Recent human cluster in Indonesia not a major genetic shift • Bad news • H5N1 virus continues to circulate widely in Asia, Europe and Africa • Eradication of H5N1 in birds is difficult

25. “Pandemic Watch”United States • No reported cases of H5N1 • Migratory birds • Poultry • Humans • Other avian influenza viruses detected in poultry in 2004 • H5N2 in Texas • H7N2 in Maryland

26. Impact of an Influenza PandemicNorth CarolinaPlanning Assumptions • 1.4 million outpatient visits • 29,000 hospitalizations • 6,700 deaths • Assuming 30% attack rate and NC population of 8.5 million people • Based on CDC software FluAid 2.0

27. Pandemic Influenza Planning • Goals • Reduce morbidity • Reduce mortality • Reduce social disruption

28. Pandemic Influenza Planning • Challenges • Widespread • Long duration • Health services overwhelmed • Shortages may occur • Medications • Equipment • Hospital beds • Personnel

29. Pandemic Preparedness Activities • NC Pandemic Influenza Response Plan • Exercises • Eight tabletop exercises Jan-Feb 2006 • Statewide full scale exercise May 2006 • Total of 185 pan flu exercises 2006-2007 • Pandemic Influenza Ethics Task Force • Federal Supplemental Funding

30. North Carolina Pandemic Influenza Response Plan • Collaboration among many different groups • First version posted to website October 2004 • Modeled after other plans • National Planning Guide (CDC) • NC SARS Response Plan • Revised version completed January 2006 • Pandemic COOP May 2007

31. Core ComponentsNC Pandemic Plan • Command and Control • Surveillance • Vaccine Preparedness and Response • Antiviral Preparedness and Response • Medical Surge • Preparedness in Healthcare Facilities • Communication

32. AppendicesNC Pandemic Plan • Supplements to core parts of plan • “Stand alone” appendices • Laboratory diagnosis • Community containment • International travel guidelines • Mass fatality plan • Legal issues • Mental health

33. Local Health Department ToolkitNC Pandemic Plan • Roles by pandemic phase • Determination of county-level impact • Influenza vaccine estimation • Designation of alternate care sites • Collaborations with local partners • Emergency Plans for Vulnerable Populations

34. #1 No intervention #2 Daily Cases With interventions #3 Days since First Case Goals of Community Mitigation in a Pandemic • Delay and flatten outbreak peak • Reduce peak burden on healthcare infrastructure • Reduce number of cases • Buy time

35. Community Mitigation of Influenza:Epidemiologic Data • School closure helpful in flu outbreak, Israel • Significant decreases in children’s diagnoses of respiratory infections (42%), visits to physicians (28%), emergency departments (28%), and medication purchases (35%). • Flu immunizaton of schoolchildren associated with lower population illness rates • Controlled trial, small towns in Michigan, 1968-69 • Immunization of children in Japan, 1962-87 • Lower rates of isolation of influenza and other respiratory viruses in Hong Kong in SARS • Many social distancing measures, public mask use Reference: WHO Writing Group. Emerg Inf Dis 2006;12:81-7

36. Community Mitigation of Influenza:Historical Information from 1918 • Forced isolation, quarantine, social distancing, masks, travel restrictions seemed ineffective in 1918, but unclear if partially effective • WHO Writing Group. Emerg Inf Dis 2006;12:88-94 • Recent hypothesis: Varying death rates in US cities may have been due to differential implementation of mitigation measures • Further historical study in progress • Markel H, Univ. of Michigan

37. Weekly mortality data provided by Marc Lipsitch (personal communication)

38. Summary: Community Mitigation of Pandemic Influenza, TLC • Home isolation of ill patients not needing hospitalization • Voluntary home quarantine for household contacts • Social distancing measures • School closure and protective sequestration of children may have profound impact • Workplace COOP (liberal leave vs. closure) • Limit public gatherings • Personal infection control measures • Hand hygiene and cough etiquette • Mask use for ill persons • Disinfection of contaminated surfaces • Antivirals for treatment & targeted prophylaxis

39. Pandemic Influenza PlanningOngoing Issues • Strengthen local health department plans • Exercise pandemic influenza plans • Increase situational awareness outside of public health • Encourage planning among other entities • Businesses • Schools • Volunteer organizations (Vulnerable Populations)

41. www.ncpublichealth.com

42. www.ReadyNC.gov

43. Online Resources • www.who.org • www.cdc.gov • www.pandemicflu.gov • www.ncpanflu.gov • www.ncpublichealth.com • www.readync.org • pandemicflu.plan@ncmail.net

44. Conclusions • Forecasting the next pandemic is difficult • Current outbreaks of H5N1 pose an ongoing threat • Pandemic influenza presents unique challenges for planners • Many different entities need to plan • Everyone has a role

45. Prevention and PlanningIt Begins At Home • The more you prepare yourself and your family, the more likely you can fulfill roles in an emergency

46. Questions? Thank you Steve Cline, DDS,MPH Deputy State Health Director NC Division of Public Health