1 |1 | Situation Update Influenza A (H1N1), 26 May 09

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3 |3 | Age distribution of confirmed new influenza A (H1N1) cases in Mexico and United States, 2009 (cases reported to 12 May)

4 |4 | Public health emergency of international concern Pandemic Phase 4 Pandemic Phase 5

5 |5 | Reasons for concern about Influenza A (H1N1) New strain- combination of swine-avian-human influenza viruses Evidences for sustained human-to-human infection –cases with no evidence of exposure other than infected humans (most cases reported so far) –clusters of cases in family members (USA, Mexico) Young people; median age of cases: 22 years

6 |6 | Influenza A (H1N1): Virology Reassortment - four different genes: –North America swine –Asia/Europe swine –Human influenza –Avian (Non H5) Unique combination that has never been seen before Level of immunity in general community –Unknown, probably limited or none Effectiveness of seasonal influenza vaccine –Unknown Antiviral resistance –Resistant to amandatines –Sensitive to oseltamivir (tamiflu) and zanamivir (relenza)

7 |7 | Pandemic Phases Sustained H-2-H transmission Time Predominantly animal infections; Limited infections of people Geographic spread Post Peak Post Pandemic

8 |8 | Phase 5 Phase 5 is characterized by the same identified virus that has caused sustained community level outbreaks into at least two countries in one WHO region. the declaration of Phase 5 is a strong signal that a pandemic is imminent the time to finalize the organization, communication, and implementation of the planned mitigation measures is short; Each country should implement actions as called for in their national influenza pandemic preparedness plans.

9 |9 | Phase 5 to Phase 6 Phase 6 is characterized by community level outbreaks in at least one other country in a different WHO region by the same virus Designation of this phase will indicate that a global pandemic is under way. Means expansion to newer area not an indication of it’s severity  Member countries should review surge capacity and emphasize measures to reduce the spread of disease  Surge capacity: in the area of surveillance, rapid detection, lab diagnosis, hospital and health centres, community awareness and empowerment etc.

10 | Lesson learned so far… Past experiences show influenza viruses spread fast and far (such as seen in 1918, 1957, 1968) Pandemic influenza may be observed in several waves, i.e. milder form to severe form Need to review Pandemic Preparedness Plan which were developed with AI (H5N1) in mind; H5N1 still around Miscommunication and misinterpretation of the events are a real challenge, i.e. travel ban, culling of pigs, import ban and remove pork from menu Knowledge gaps exist on current pandemic from novel influenza A (H1N1)- as it is evolving

11 | Influenza Seasonality Pune (west) Kolkota (east) Chennai (south) Delhi (north)

12 | WHO/SEARO Response Situation monitoring and assessment Technical guidance Capacity building: surveillance and laboratory diagnosis Vaccine and antivirals Communication –media briefing, interviews, web updates etc

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