1. Dr. Jarbas Barbosa Area Manager Health Surveillance & Disease Prevention and Control

2. Timeline (1) April 10: an outbreak of influenza-like illness in Veracruz, Mexico detected. April 11: PAHO IHR requested verification. April 12: Mexican government confirmed outbreak investigation. April 16: A case of atypical pneumonia in the Mexican state of Oaxaca triggered enhanced surveillance April 18: two cases of the new A (H1N1) virus infection identified in two southern California counties in USA.

3. Timeline (2) April 23: new influenza A (H1N1) virus infection confirmed in several patients in Mexico. April 26: 38 cases reported by Mexico and the USA April 27: Canada and Spain reported first confirmed cases April 28: UK, Israel, New Zealand April 27: WHO declared phase 4 April 29: WHO declared phase 5 June 11: WHO declared phase 6 – pandemic In 9 weeks: all WHO regions reporting cases of pandemic (H1N1) 2009

4. Epidemiology of Pandemic (H1N1) 2009 Virus Infection

5. Poultry Wild birds Avian influenza virus Human Emergence of a pandemic Seasonal influenza virus A (H5N1) New virus (reassortment) Influenza pandemic Pig

6. Pandemic (H1N1) 2009 Number of laboratory confirmed cases as reported to WHO (18 April to 30 August 2009) 18 April 2009 30 August 2009

7. Number of confirmed cases and deaths Pandemic (H1N1) 2009 Communicate directly to IHR Point of Contact at WHO Regional Office (ihr@paho.org)ihr@paho.org Worldwide = Widespread geographic distribution –188 countries and territories affected – at least 2,837 deaths in 62 countries (cumulative numbers as of August 30, 2009) In the Americas: –35/35 countries affected –120,629 confirmed cases and 2,467 deaths as of September 3, 2009, 16:00

8. ►All viruses to date are homogeneous antigenically and react well with antisera raised against California/4/2009 and California/7/2009 ►To date, no recognized genetic markers associated with virulence (Viruses isolated from severe cases do not show sequence differences) ►Virus replicates more in lungs and causes more severe pneumonia in animals (ferrets, mice, primates) than seasonal H1N1 (unpublished) Pandemic (H1N1) 09 virus characteristics

9. Confirmed Cases in Argentina by date of onset Initial spread in large cities

10. Distribution of confirmed pandemic influenza A (H1N1) 2009 cases by age group in selected countries Source: Ministries of Health of the countries in the Region

11. Hospitalized or severe confirmed cases CountryCanadaChileBrazil Reporting period Through week 33 Through August 26, 2009 Through week 33 Reporting of severe or hospitalized cases Hospitalized cases Severe cases Number of hospitalized or severe confirmed cases analyzed n=1441n=1480n=5206 % Female 51.651.0-- Median age in years 2531-- % Pregnant 27.9 1 --29.7 2 % Co-existing medical conditions 57.2 3 46.036.9 4

12. Deaths among confirmed cases ArgentinaBrazilCanada ChileCosta Rica MexicoPeru Reporting period Until EW31Until EW32Until EW31 Until EW32 Until EW29 N404368661052816429 Sex “No differences” - 63.1% female (41/65) 48. 6% female (48/104) 53.6% female (15/28) 49.4% female 48.3% female (14/29) Age Most affected group 50-59 years - Median 51 years Median 49 years (range 4m-89y) Median 41 years 63.2% between 20–49 years 62.0% between 20- 50 years % Co- morbidities 32%50.3%81.3% (39/48) 66.6% (70/105) --37.9% [1][1] Most frequent co-morbidities Obesity (14.3%) Cardiopathies (11%) Cancer (8%) COPD (8%) Metabolic diseases Respiratory illnesses Chronic cardiopathies -- Obesity (42.9%) Diabetes Mellitus (25%) Asthma (21%) COPD (10.7%) Metabolic diseases (34.8%) Smoking (23.2%) Cardiopathies (15.9%) - Pregnancy28% (26/90) [2] [2] 29.9% [3] (46/154) [3] 18.2% [4] (2/11) [4]-10.7% [5] [5] -- [2] Age range for the 90 women in childbearing age not specified. Numerator includes pregnant and puerperal women. [3] Among women between 15 and 49 years old [4] Among women between 15 and 44 years old. [5] Not specified if this percentage is among total deaths or among total deaths women in childbearing age

13. Distribution of respiratory virus by epidemiological week (EW), Chile EW 1-34 JanFebMarApr May Jun Jul Aug Epidemiological week Source: Chile Ministry of Health

14. Distribution of respiratory virus by age group. Argentina, January- September 2009 Source: Argentina Ministry of Health

15. Distribution of outpatient visits by Epidemiological Week in different regions of Chile. % of cases per Region National Rate (100,000 hab) Source: Chile Ministry of Health

16. 60% of the confirmed cases being detected in persons with less than 20 years of age. Hospitalized cases and deaths occurred in adults. Hospitalization and case/fatality in young adults higher than seasonal influenza. Epidemiologic and serologic evidence for low susceptibility in older adults. At-risk groups: Pregnant women, people with chronic diseases and underlying health conditions, young children, people with immunosuppression. Replacement of influenza seasonal virus. Epidemiology of Pandemic (H1N1) 2009 Virus Infection Source: WHO

17. WHO Surveillance Guidelines For countries not yet affected: –Document first appearance of the pandemic virus and to collect sufficient information for risk assessment. Once affected: –Detect any changes in the epidemiological, virological or clinical presentation. Unusual or unexpected public health events, e.g. clusters of severe unexplained acute respiratory illness or unexplained deaths.

18. Qualitative Indicators for the monitoring of Pandemic (H1N1) 2009 IndicatorCriteria Geographical spread No activityLocalizedRegionalWidespread TrendIncreasingUnchangedDecreasing IntensityLow or moderateHighVery high ImpactLowModerateSevere

23. Monitoring of Respiratory Disease Activity in Americas Region Northern Temperate zone: –US and Canada: Overall, low levels of ILI activity, below epidemic threshold. –Increasing ILI activity in the southeastern US. –In Canada, 11-17% of severe cases are indigenous. Southern temperate zone: –Chile and Argentina: Continued regional to widespread geographic activity; –The majority of respiratory virus detections are now due to Respiratory Syncitial Virus (RSV).

24. Equatorial South America: –Bolivia, Ecuador and Venezuela: Continue to experience widespread geographic influenza activity with increasing respiratory disease trend in most countries. –Brazil: Regional geographic activity, especially in later affected tropical areas. ILI consultations (15% of all visits) are falling, but remain significantly above seasonal historical average. Tropical Central America: –Costa Rica, El Salvador, Guatemala, Honduras and Panama: Continue to experience widespread geographic influenza activity, but the respiratory disease trend is now beginning to decrease. Impact on the healthcare system continues to be moderate. Monitoring of Respiratory Disease Activity in Americas Region

25. Clinical presentation and evolution

26. Short incubation period (1-2(-4) days) Onset of the disease usually abrupt with: - Typical systemic symptoms: high fever and chills(94%) severe malaise fatigue and weakness headache or myalgia –Respiratory tract signs: non-productive cough (92%), sore throat (66%), and rhinitis –Gastrointestinal manifestations: diarrhea and vomiting (25%) Emergence of a Novel Swine-Origin Influenza A (H1N1) Virus in Humans. N Engl J Med 2009;360. Initial Clinical Presentation

27. Complications - Severe cases Predominant age group: 20-59 years Age range 1-80 years Sex ratio: 1 Underlying conditions: 60-80%  COPD, asthma  diabetes,  cardiovascular disease  pregnancy  obesity Signs and symptoms -Dysnea -Cough -Hemopthysis Investigation findings -Chest x-ray: multilobar infiltrates (100%) -Sat O2: < 90% (100%) - Renal failure and/or hepatic affectation (50%) Multiorganic failure

28. Complications - Severe cases Diagnosis: Primary influenza pneumonia Complications: Mechanical ventilation secondary pneumonia Antiviral treatment in severe cases: - After 7 days of initiation of symptoms: worse evolution - 1 – 3 days of initiation of symptoms: better outcome Source: Dr. Luis Septien Stute. Hospital General de Mexico Source: MoH Argentina, Canada, Chile, Dominican Republic, Mexico, Uruguay and USA

29. Estimated by data pooling Percentages calculated on the immediate lower step Deceased? 1.4 – 5% 20% 35% ? Source: MoH Argentina, Canada, Chile, Dominican Republic, Mexico, Uruguay and USA

30. Age-related distribution of deaths from severe pneumonia compared to influenza seasons 2006-08 (Mexico, 24 March- 29 April 2009) During 5-weeks period, 2155 cases of severe pneumonia with 821 hospitalizations + 100 deaths: 87% of deaths and 71% of severe pneumonia cases aged 5- 59 yrs

31. Key challenges Identification of predictors for severity among young adults with no underlying diseases. Oseltamivir resistance surveillance. Algorithms for clinical management of severe cases.

32. WHO-SAGE recommendations on pandemic (H1N1) 2009 vaccines- 7 th July 09 ►Health-care workers as a first priority to protect the essential health infrastructure ►SAGE suggested the following groups for consideration (countries need to determine their order of priority based on country-specific conditions): Pregnant women Above 6 months with one of several chronic medical conditions Healthy young adults of 15 to 49 years of age Healthy children; Healthy adults of 50 to 64 years of age and Healthy adults of 65 years or above. ►Post-marketing surveillance of the highest possible quality ►Promoting production and use of vaccines formulated with oil-in-water adjuvant and live attenuated influenza vaccines.

33. International Passenger Departures from Mexico March 1st to April 30th 2008 N Engl J Med 361(2):212-4 (July 9, 2009) Risk assessment: Mapping destinations of flights

34. PAHO/WHO Response to A/H1N1 in the Americas

35. PAHO has been working with countries since 2004 on pandemic preparedness and on the International Health Regulations. Is tracking the regional situation and advising countries on surveillance, laboratory and infection control measures required to identify and treat cases and trace contacts. Has mobilized experts to several countries of the Region in epidemiology, virology, laboratory analysis, infection control, emergency response, logistics, risk communication; including actualization of treatment guidelines. Has distributed laboratory diagnostic kits through Collaborating Centers to National Influenza Centers. What is PAHO doing?

36. Has deployed a stockpile of Oseltamivir (Tamiflu) to countries in the Region. Weekly teleconferences with Ministries of Health and Epidemiology Chiefs of all countries in the Region. Provides risk communication support to countries. Weekly publication of regional updates including qualitative indicators. Development of technical guidelines and translation, publication and dissemination of WHO materials. Mobilizing additional resources. What is PAHO doing?

37. What should countries do? Adapt plans and interventions to the current pandemic, which is assessed as moderate. Calibrate their response to the current severity assessment. Implement public health measures based on the epidemiological situation Continue monitoring for increases in severity, genetic changes and strengthening health systems to ensure continuity and rapid adjustments.

38. Pandemic (H1N1) 2009 Summary So far, high but variable transmissibility in countries. 5-45 years old people most commonly affected. Hospitalization rates and case-fatality in young adults higher than during seasonal influenza. Co-circulation of seasonal and pandemic viruses. Groups at risk for severe illness: pregnant women; those with asthma, obesity, chronic heart or lung disease, cancer, immunosuppression. Source: WHO

39. Pandemic (H1N1) 2009 Summary In the Northern Hemisphere transmission is expected to increase during fall and winter. Every country needs to be prepared for this situation in the following areas: –Surveillance –Public health measures –Health services –Antivirals and vaccines –Risk communication

40. Thank you Please visit PAHO Pandemic (H1N1) 2009 web page for regular updates: www.paho.org