Influenza A (H1N1)

1. Influenza A (H1N1)

2. Influenza is usually a respiratory infection Transmission Regular person-to-person transmission Primarily throughcontact with respiratory droplets Transmission from objects (fomites) possible National Center for Disease Prevention and Control, DOH

3. Key Characteristics Communicability Viral shedding can begin 1 day before symptom onset Peak shedding first 3 days of illness Correlates with temperature Subsides usually by 5-7th day in adults Infants, children and the immuno-compromised may shed the virus longer National Center for Disease Prevention and Control, DOH

4. Incubation period Time from exposure to onset of symptoms 1 to 4 days (average = 2 days) Seasonality In temperate zones, sharp peaks in winter months In tropical zones, circulates year-round with seasonal increases. National Center for Disease Prevention and Control, DOH

5. Individuals at Increased Risk for Hospitalizations and Death Elderly >65 years Children less than two years Certain chronic diseases Heart or lung disease, including asthma Metabolic disease, including diabetes HIV/AIDs, other immuno-suppression Conditions that can compromise respiratory function or the handling of respiratory secretions Pregnant women National Center for Disease Prevention and Control, DOH

6. INTENSIVE-CARE PATIENTS WITH SEVERE NOVEL INFLUENZA A (H1N1) VIRUS INFECTION --- MICHIGAN, JUNE 2009 10 patients wiith Influenza A(H1N1) and ARDS admitted at ICU. Of the 10 patients 9 were obese (BMI>30) including 7 who are extremely obese (BMI>40). Five had pulmonary emboli; Nine had MODS. 3 patients died. Clinicians should be aware of the potential for severe complications of H1N1 virus infection in extremely obese patients.

7. Conclusion • Predominance of males • High prevalence of obesity • Frequency of clinically significant pulmonary emboli and MODS

8. Influenza A Viruses Influenza A viruses categorized by subtype Classified according to two surface proteins Hemagglutinin (H) – 16 known Neuraminidase (N) – 9 known N H National Center for Disease Prevention and Control, DOH

9. A / Sydney / 05 / 97 (H3N2) Nomenclature Strain number Virus subtype Virus type Place virus isolated Year isolated National Center for Disease Prevention and Control, DOH

12. Influenza A (H1N1) is a novel virus • Unusual combination of genetic material from pigs, birds & humans which have re-assorted • Affects all age groups • Vaccines for human seasonal flu can not protect humans against the novel virus National Center for Disease Prevention and Control, DOH

13. Swine Influenza Viruses • RNA viruses • Pigs can be infected by avian influenza and human influenza viruses as well as swine influenza viruses. • Re-assort and new viruses that are a mix of swine, human and avian influenza viruses can EMERGE National Center for Disease Prevention and Control, DOH

14. Genetic Re-assortment SIV National Center for Disease Prevention and Control, DOH

15. Signs & Symptoms of Influenza A (H1N1) • Fever • Lethargy • Lack of appetite • Coughing • Runny Nose • Sore throat • Nausea / Vomiting • Diarrhea National Center for Disease Prevention and Control, DOH

16. Swine H1N1 vs. Human H1N1 • swine H1N1 flu virus NOT the same as human H1N1 virus • antigenically very different from human H1N1 viruses • vaccines for human seasonal flu can not protect humans from swine H1N1 National Center for Disease Prevention and Control, DOH

17. Transmission: Food-Borne? • NO • Influenza A (H1N1) viruses are not transmitted through food • Safe to eat properly handled and cooked pork and pork products • Cook pork at an internal temperature of 70°C (160°F) National Center for Disease Prevention and Control, DOH

18. Diagnosis and Laboratory Confirmation • Clinically diagnosed • Respiratory Specimen • first 4 to 5 days of illness • can shed for 10 days or longer • Specimens sent to US CDC • ONLY laboratory that can isolate and identify swine influenza type A virus National Center for Disease Prevention and Control, DOH

19. Specimens • Upper respiratory tract specimens as recommended are the most appropriate. • taken from the deep nostrils (nasal swab), nasopharynx (nasopharyngeal swab), Nasopharyngeal aspirate, throat or bronchial aspirate.

20. Laboratory Diagnosis Rapid Influenza Diagnostic Test • Antigen detection test that detect influenza viral nucleoprotein antigen • Can provide results within 30 minutes • Sensitivity 40-69%

21. CDC rRT-PCR Swine Flu Assay • Sensitivity : 99.8% • Specificity: 92%

23. Treatment • Influenza A (H1N1) is sensitive to: • Oseltamivir (tamiflu) • Zanamivir • Self medication is discouraged, may induce drug resistance • Chemoprophylaxis • Oseltamivir National Center for Disease Prevention and Control, DOH

25. CDC Health Advisory • Distributed via Health Alert Network July 09, 2009 Three Reports of Oseltamivir Resistant Novel Influenza A (H1N1) Viruses

26. ANTI VIRAL CHEMOPROPHYLAXIS • Post-exposure prophylaxis for health care workers, first responders and workers who did not have adequate PPE when in contact. • Anti-viral prophylaxis is not recommended to close contacts except when they belong to high risk group.

27. Vaccine • Process of production is underway, but may take 5 – 6 months • Seasonal influenza vaccine provides protection against the seasonal human influenza strains only National Center for Disease Prevention and Control, DOH

28. Vaccine 0.5 mL doses contain 15 µg hemagglutinin of the vaccine strain A/California/7/2009 (H1N1)Two doses separated by 4 weeks for children 2-9 years(CDC. Update on influenza A (H1N1) monovalent vaccines. MMWR Morb Mortal Wkly Rep. 2009;58:1100-1101.)

33. INTERIM GUIDELINES NO.2: INFECTION CONTROL AND USE OF PERSONAL PROTECTIVE EQUIPMENT IN INFLUENZA A HEALTH CARE PERSONNEL • Standard and droplet precautions when working in direct contact • If there is risk of splashes: particulate respirator; eye protection;clean, non-sterile, long sleeved gown; sterile gloves • Frequent and proper handwashing

34. Isolate patient in a single room. Reinforce standard precautions with droplet and contact precaution Use appropriate Personal Protective Equipment for all those entering patients rooms. Restrict number of visitors. Healthcare workers on direct contact should monitor their own temperature 2X a day and report any febrile event.

35. INTERIM GUIDELINES NO.17: REVISEDCLINICAL CASE MANAGEMENT OFINFLUENZA A(H1N1) VIRUS INFECTION

39. Vaccination Influenza vaccine is the best prevention for seasonal influenza. Inactivated viruses in the vaccine developed from three circulating strains (generally 2 Type A and 1 Type B strain) Therefore, seasonal “flu shot” only works for 3 influenza subtypes and will not work on pandemic strains. Live, intranasal spray vaccine for healthy non-pregnant persons 5-49 years Inactivated, injectable vaccine for persons 6 months and older National Center for Disease Prevention and Control, DOH

40. Influenza Viruses Classified into types A, B, and C Only Types A and B cause significant disease Types B and C limited to humans Type A viruses More virulent Affect many species C Goldsmith, CDC National Center for Disease Prevention and Control, DOH

41. The FDA has approved 4 vaccine preparations. The following data highlight relevant issues: All influenza vaccine preparations in the United States for the 2009-2010 season contain residual egg protein and none contain adjuvant; Children 6 months to 9 years of age who are given influenza A (H1N1) monovalent vaccine should receive 2 doses separated by about 4 weeks; persons ≥ 10 years of age should receive 1 dose; The influenza A (H1N1) monovalent vaccines were made according to standards used for seasonal and influenza vaccines and have the same age group indications, precautions, and contraindications as vaccines that are FDA-approved for seasonal flu; preliminary data indicate that the safety and efficacy of the 2009 Influenza A (H1N1) monoclonal vaccine is the same as winter; There is minimal evidence of significant antigenic change since the first characterization of the virus in April 2009, indicating that the virus continues to be well matched with the vaccine strain; and The vaccines of the 4 suppliers have some differences that are important to recognize:for seasonal flu vaccines; Side effects, including local pain at the injection site, were reported in 46% of recipients, and systemic reactions (headache, malaise or myalgias) were reported in 45%; the safety profile is consistent with the experience with seasonal flu vaccine; Influenza activity due to influenza A (H1N1) increased in September 2009 and is expected to continue through fall and

42. Children 6 months to 9 years of age should receive 2 doses separated by 3 weeks. Children 10 years and older and adults should receive 1 dose. • The following groups should receive the vaccine as soon as it becomes available: • Pregnant women; • People who live with or care for infants younger than 6 months of age; • Healthcare workers (HCWs) and emergency medical personnel; • Persons 6 months to 24 years of age; • Persons 25-64 years of age who have chronic diseases (including immunodeficiency states) that pose risk for influenza. • When more vaccine becomes available, the following persons should be vaccinated: • Healthy persons ages 25-64 years; and • Adults 65 years of age and older.

43. S-top spreading panic acts / thoughts. T-amiflu panic buying (Avoid). O-ver-reacting with vaccines. P-rotective Equipments S-ocial Distancing. W-ASH YOUR HANDS I-solate voluntarily. N-o Unnecessary travel. E-arly Consult. F-lu symptom declared. L-imit Crowded areas. U-pdate yourself. H1N1 - Dos & DON’Ts ! N. Macalintal Jr. MD, FPCP, FPCCP