DR MOSES MWANGI HSC Regional Manager, Sanofi pasteur Eastern Africa

Transcription

1 IINFLUENZAE & PNEUMOCOCCAL DISEASES,A CASE FOR PREVENTIVE APPROACH THROUGH VACCINATION AE & PNEUMO VACCINES ARE ESSENTAL PILLARS DR MOSES MWANGI HSC Regional Manager, Sanofi pasteur Eastern Africa 1 1

2 Often misunderstood and underestimated, Influenza is not just a bad cold! Annual, winter influenza epidemics Influenza pandemics: exceptional epidemiological events occurring every few decades 2 2

3 Influenza virion Capsid (type A, type B, type C) PB2 PB1 PA HA NP NA M NS Neuraminidase (NA) Haemagglutinin (HA) Surface antigens Protective antibodies Envelope 3 3

4 Influenza virus mutations Influenza type A viruses mutate frequently, type B viruses mutate less frequently, Mutation enables the virus to bypass the population s acquired immunity Both the haemagglutinin and neuramidase surface antigens mutate Mutation occur through two mechanisms Antigenic drift Occurs continually Leads to modified viruses that causes annual epidemics Antigenic shift Occurs rarely Leads to novel viruses that cause pandemics Betts FR, Douglas RG, Mandell G.L., Douglas R. G., Bennett J.E., Principles and practice of infectious diseases, 3rd ed., 1990;39:

5 Transmission Virus is mainly spread through the air by coughing and sneezing, especially in closed public places: public transport, meeting rooms,... An infected person can transmit the virus to others from 1-2 days before flu symptoms start, and for 5 days afterwards 5 5

6 INFUENZAE IS A GLOBAL PROBLEM, CIRCULATION IS NOW WELL DOCUMENTED IN KENYA: About 5 to 10 % of the world s population catches influenza every year. This means 500 million people Responsible for 3 to 5 million serious cases At least 500,000 reported deaths each year Influenza does not discriminate: Affects all age groups, BUT more severe in the Very young, the Elderly and those with underlying medical conditions. In Kenya Peak incidence coincide with cold weather 6 6

7 Complications Mainly affect the elderly and infants Infants Otitis Media, either viral or a secondary bacterial infection Exacerbation of chronic asthma More rarely: high fever and convulsions Myositis Adults Bronchitis, sinusitis Fulminant viral pneumonia (seen during influenza pandemics) Elderly persons and those with high-risk chronic medical conditions Acute bronchitis Pneumonia: viral or secondary bacterial infection Respiratory (asthma), cardiac, renal or metabolic (diabetes) DECOMPENSATION Treanor JJ. Orthomyxoviridae: Influenza virus. In: Mandell GL, Bennette JE, Dolin R, editors. Principles and practice of infectious diseases. London: Churchill Livingstone, 2004:

8 International surveillance network Choice of vaccine strains procedure Sentinel Doctors Isolation of strains National influenza Centers (over 110 national laboratories in over 80 countries) Collaborating Reference Centers for Research against influenza (London, Atlanta, Tokyo and Melbourne) World Health Organization (WHO - Geneva) Vaccine Manufacturers Hannoun C. Role of international networks for the surveillance of influenza. Eur Journal of Epidemiol 1994;10:

9 Seasonal influenza vaccines 2011 FORMULA FOR South Hemisphere and also coming North Hemisphere A/California/7/2009 (H1N1)-like virus A/Perth/16/2009 (H3N2)-like virus B/Brisbane/60/2008-like virus 9 9

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11 VAXIGRIP in practice International schedule Age group Vaccination every year 0.25 ml 0.5 ml Presentations 6 to 36 months old over 3 years old 1 dose of vaccine in a prefilled syringe 11 11

12 Influenza in at risk patients Asthmatics Diabetics At risk patients 12 12

13 Influenza in asthmatic patients 1 Association of respiratory viral infections with asthmatic crisis in adults 138 adults with asthma 10/90 to 08/92, UK > 40% of symptomatic asthmatic crisis were associated with viral respiratory infections 71% of the crisis were associated with cold symptoms Influenza was associated with severe crisis Nicholson et al., BMJ, 1993 Influenza is a severe disease for asthmatics 2 Does flu vaccination induce crisis in asthmatics?? 12,000 patients years old with asthma and COPD, 3 flu seasons Tata et al., Thorax, 2003 Asthma diagnosis as well as corticosteroid prescriptions are the same after vaccination and during low risk season Asthmatic crisis do not increase significantly after vaccination Influenza vaccination does not induce asthma crisis in adults 13 13

14 Flu vaccination prevents asthma crisis asthmatic children 0-12 years 2 influenza seasons All children 27% reduction in acute respiratory attacks 56% reduction during first influenza season Children < 6 years 55% reduction in acute respiratory attacks 77% reduction during second influenza season 2 Smits et al., Epidemiol Infect, asthmatic children 1-6 years 3 seasons (USA) Kramarz et al., J Pediatr, 2001 A sth m a crisis re d u c fir s t s e a s o ns e c on d s e a s o nth ir d s e a s o n 14 14

15 Influenza risks in diabetics Diabetics are 6 times more at risk to be hospitalized with an influenza diagnosis 3 times more at risk of dying of pneumonia or influenza Mortality rate increases by 5 to 15% during influenza epidemics CFR for influenza: 12% Immune response Response is satisfactory in 70% of patients Patients who don t respond to initial immunization respond to a second dose Influenza consequences in diabetics are very severe Immunization is very valuable in these patients 15 15

16 Effectiveness of influenza vaccination in diabetic patients psoh ssecxe ict eb ia d in sht ati s azil sn iot dna aed v a c c in a te du n v a c c in a t Effectiveness of influenza vaccination in the reduction of the risk of hospitalization for influenza or pneumonia, or death 50% in % in In a case control study, influenza vaccination reduced hospitalization: For pneumonia and influenza by 80% For bronchitis For diabetis without mention to any complication For diabetic comas For acidocetosis Influenza vaccination was EFFECTIVE since it reduced hospitalizations during influenza epidemics 16 16

17 Influenza and cardiovascular diseases (CVD) Flu activity and hospital admissions for heart failure In people older than 65 years, Hong Kong, In 2002, CVD represented 29.2% (16.7 millions) of worldwide deaths Global CVD impact increases (increase in population age, urbanization) Hospital admission for heart failure Influenza activity Jan Jun Dec Jan Jun Dec Jan Jun Dec Jan Jun Dec 0 Obvious superposition between the flu activity peak and heart failure hospitalizations 17 17

18 Benefits of flu vaccination in patients with CVD FLUVACS study (Argentina): flu vaccination and reduction of death and ischemic events in patients with Myocardial infarction Significant reduction in deaths (75%) and rehospitalizations Reduction of the triple risk (CV deaths, infarction and severe ischemia) Consistant results during 2 years, and with other studies Four case control studies: reduction of: 49% for primary cardiac arrest risk 67% for the MI risk 55% for cerebral stroke (2 studies) CONCLUSION: Flu vaccination is associated with a reduction in the risk of CV events 18 18

19 Groups at increased risk for Influenza-related Influenza complications vaccination is the primary method for preventing influenza and its severe complications. The Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for the following groups: Persons at high risk for influenza-related complications and severe disease, including Children aged under 5 years, Pregnant women, Persons aged >50 years, Persons of any age with certain chronic medical conditions; and Persons who live with or care for persons at high risk, including Household contacts who have frequent contact with persons at high risk and who can transmit influenza to those persons at high risk and Health-care workers. (1). CDC. Prevention and control of influenza. Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR July 29, 2006;54: RR

20 Influenza Vaccination: The best defence against illness for more than 50 years Effective Vaccination mimics natural infection, providing protection for 6-12 months against the vaccine strains Protects 70 90% of vaccinated healthy adults Reduces complications and mortality by % in elderly persons Beneficial to society Vaccination reduces the risk of transmitting the virus to others: Persons at risk of complications of influenza infection (the elderly, infants ) Family, friends, colleagues 20 20

21 Current influenza immunization rates are very different around the world (17) FedsonDS. Themacroepidemiology of influenza vaccinationin56 countries, : areport fromthemacroepidemiology of influenza vaccination(miv) StudyGroup. Vaccine, 2005, InPress, UncorrrectedProof

22 The threat of Pandemics A/H1N1-Swine flu may not have become as serious. A/H5N1-Avian Flu!! 22 22

23 Pneumococcal Polysaccharide Vaccine

24 Sanofi Pasteur s Pneumococcal Polysaccharide Vaccine 23-Valent pneumococcal polysaccharide vaccine Each 0.5 ml dose contains: [1a] 25 µg of 23 purified pneumococcal capsular polysaccharide types Available presentations: [1b] Single-dose prefilled syringes or multidose vial Routes of administration: [1c] Intramuscular (IM) or subcutaneous (SC) Pneumococcal vaccine may be administered concomitantly with influenza vaccine using different syringes and injection sites [1d,2,3] [1] Sanofi Pasteur, Pneumo 23 product prescribing information. June 2005 [2] Honkanen et al. Arch Intern Med 1996, 156 (2) [3] Grilli et al., Eur J Epidemiol Apr;13(3) 24

25 Polysaccharide Pneumococcal Vaccine is Effective against IPD among Patients with asthma and chronic obstructive pulmonary disease US CDC* data analysis for the estimation of pneumococcal vaccine efficacy against IPD among specific at-risk groups (US, ): Diabetes mellitus (9/122) 95% CI: 50-95% 84% Anatomic asplenia (89/23) Coronary vascular dis. (15/73) Congestive heart failure (20/96) 95% CI: 14-95% 77% 95% CI: 23-90% 73% 95% CI: 17-88% 69% Pulmonary disease* (50/186): 95% CI: 26-83% 65% *Asthma and chronic obstructive pulmonary disease 95% CI: 57-85% 75% Immunocompetent 65 years (70/373) Underlying illness (N isolates in vacc./unvacc.) Vaccine effectiveness against IPD (%) 65% efficacy in patients with pulmonary disease [1a] * CDC: Centers for Disease Control and Prevention [1] Adapted from Butler et al. JAMA, 1993;270(15) 25

26 ACIP recommendations for polysaccharide pneumococcal vaccine Groups for which vaccination is recommended Revaccination Persons aged >65 years 5 years since 1 st dose AND age <65 years at 1 st dose: single revaccination Persons aged 2-64 years with chronic illness Chronic cardiovascular, pulmonary, liver disease Diabetes mellitus, CSF leaks, alcoholism with anatomic/functional asplenia (e.g. sickle cell disease, splenectomy) Not recommended Age >10 years: single revaccination 5 years after previous dose Age 10 years: consider revaccination 3 years after previous dose with immunocompromising conditions: HIV infection Leukemia, lymphoma, immunosuppressive therapy living in special environments/social settings Residents of nursing homes & long-term care facilities 5 years since 1 st dose: 1 revaccination Age 10 years: consider revaccination 3 years after previous dose Not recommended Adapted from [1a] CDC. MMWR Recom Rep, 1997; 46(RR8) 26

27 New ACIP recommendations for asthma patients On October 22, 2008, the ACIP voted on new and revised recommendation for the use of 23-valent pneumococcal polysaccharide vaccine for the prevention of invasive pneumococcal disease. Persons aged 19 through 64 years who have asthma should receive a single dose of PPV23. The ACIP recommends that asthma should be included among the chronic pulmonary diseases (such as COPD and emphysema) that are indications for PPV23 (in persons 2-64 years old). [1] ACIP Provisional Recommendations for Use of Pneumococcal Vaccines,

28 Conclusion Asthma is a major health concern worldwide Asthmatics are at increased risk for invasive pneumococcal diseases PPV23 is effective against IPD in asthmatic patients and is recommended by the ACIP in this population (since 2008) 28

29 Conclusion Annual Flu vaccination in at risk patients should be institutionalized in Kenya between March and July. Pneumococcal disease is preventable through Vaccination with Pneumo 23 If INFLUENZAE condemns, the secondary bacterial infections executes. 29