1. Influenza biology and epidemiology

2. The course of illness  Symptoms  Fever, headache, body aches, fatigue  Cough, sore throat, runny nose  Duration: 2-7 days  Incubation period: 1-5 days  Susceptibility depends on prior exposure  Complications: bacterial infection

3. Susceptible Exposure Infection Symptoms Resolution Infectious disease progression

4. Susceptible Exposure Infection Symptoms Resolution Infectious disease progression Period of infectivity (SARS)

5. Susceptible Exposure Infection Symptoms Resolution Infectious disease progression Period of infectivity (flu)

6. The influenza virus H1N1

7. Virus mutation  Drift  Relatively minor changes in the antigens  Partial immunity to subsequent infection  Shift  Radical change in the antigens  No immunity conferred from earlier infections

8. Shift: Pandemic

10. Jumping between people and animals

11. Avian fluSeasonal and Pandemic flu Jumping between people and animals

12. Avian flu

13. Epidemic transmission

14. Animal culling

15. Treatment  Tamiflu  Relenza  After symptoms  Post exposure prophylaxis

16. Social distancing  Isolation  Quarantine  Face masks  Cancel social gatherings

17. Vaccine  This year’s seasonal vaccine based on last year’s strains  No vaccine yet for H5N1  Can’t anticipate final mutation to a pandemic strain  Development 6-8 months after pandemic strain identified

18. Preparation and response levels Country States & Provinces Cities and Counties Businesses and Civil Society Individuals and Families WHO

19. 1918: Pandemic waves

20. 1918: Illness rates by age

21. 1918: Mortality rates by age

22. 1976: Premature action