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“Vaccines: when to give… and how to mix ….” or

“Vaccines: when to give… and how to mix ….” or “Optimising immunization schedules” (the story of a complex initiative) TEG Symposium March 29-30 2012 Paul Fine LSHTM. Routine immunization – early history. Wealthy countries 19 th century - widespread smallpox vaccination

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“Vaccines: when to give… and how to mix ….” or

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  1. “Vaccines: when to give… and how to mix ….” or “Optimising immunization schedules” (the story of a complex initiative) TEG Symposium March 29-30 2012 Paul Fine LSHTM

  2. Routine immunization – early history Wealthy countries 19th century - widespread smallpox vaccination post WWII - routine childhood vaccination began eg UK diphtheria – 1941 tetanus – 1950 BCG - 1953 polio (IPV) - 1955 pertussis (nat’l) - 1957 measles – 1968 Poorer countries just smallpox ..... eradication programme from 1967 Globally – in 1974 – only 15 % of children routinely vaccinated

  3. But look what happened ! - “EPI” 1974 one of the triumphs of public health DTP 3 coverage Number of “unimmunised” children (millions)

  4. Basic EPI schedule (from 1970s)Purposefully simple To avoid maternal antibody 4-week spacing, to optimise boosting

  5. But circumstances evolved - 1975 - 2005 • Epidemiology changed • of EPI vaccine target diseases ... • Development of PHC – EPI infrastructure • From very little anywhere to basics virtually everywhere • New vaccines • Hib, HepB, JapB, Pneumo, Rotavirus, Mening.... • WHO “SAGE” (from 1999) • “Strategic Advisory Group of Experts” • GAVI (from 2000) • “Global Alliance on Vaccines and Immunization” • “Lobbies” .... • single vaccine interests • So …. some countries started to change schedules ….

  6. But circumstances evolved - 1975 - 2005 • Epidemiology changed • of EPI vaccine target diseases ... • Development of PHC – EPI infrastructure • From very little anywhere to basics virtually everywhere • New vaccines • Hib, HepB, JapB, Pneumo, Rotavirus, Mening.... • WHO “SAGE” (from 1999) • “Strategic Advisory Group of Experts” • GAVI (from 2000) • “Global Alliance on Vaccines and Immunization” • “Lobbies” .... • single vaccine interests • So …. some countries started to change schedules …. Increasing discussion on need to change the basic EPI schedule

  7. But circumstances evolved - 1975 - 2005 • Epidemiology changed • of EPI vaccine target diseases ... • Development of PHC – EPI infrastructure • From very little anywhere to basics virtually everywhere • New vaccines • Hib, HepB, JapB, Pneumo, Rotavirus, YF, Mening.... • WHO “SAGE” (from 1999) • “Strategic Advisory Group of Experts” • GAVI (from 2000) • “Global Alliance on Vaccines and Immunization” • “Lobbies” .... • single vaccine interests • So …. some countries started to change schedules …. Increasing discussion on need to change the basic EPI schedule But, reluctance.... “it’s not that broke...”

  8. But circumstances evolved - 1975 - 2005 • Epidemiology changed • of EPI vaccine target diseases ... • Development of PHC – EPI infrastructure • From very little anywhere to basics virtually everywhere • New vaccines • Hib, HepB, JapB, Pneumo, Rotavirus, YF, Mening.... • WHO “SAGE” (from 1999) • “Strategic Advisory Group of Experts” • GAVI (from 2000) • “Global Alliance on Vaccines and Immunization” • “Lobbies” .... • single vaccine interests • So …. some countries started to change schedules …. Increasing discussion on need to change the basic EPI schedule But, reluctance.... “it’s not that broke...” Until, finally....

  9. Conclusions and recommendations – SAGE 2005 “Optimizing immunization schedules: SAGE recognized the importance and timeliness of reviewing the scientific and operational basis for the choice of the optimal schedule for childhood immunization. More than 20 years have passed since the “EPI schedule” of 6, 10 and 14 weeks for DTP-OPV and 9 months for measles vaccine was introduced,and more information has accrued, together with the development of improved techniques for assessing immune responses. There was recognition that immunization schedules in use today vary greatly around the world, and it is unlikely that a single, uniform immunization schedule would suit all countries. WHO should aim to provide countries with advice on the parameters to be considered when they select a schedule. There was unanimous support for a new review of the evidence base, and agreement that changes in schedule are not appropriate without strong evidence to demonstrate benefit.” Weekly Epidemiological Record, 06/01/06

  10. Which led to .... • Discussions of how to proceed... • Meeting at LSHTM October 2008 • Development of vision and strategy • “Optimising immunisation schedules” • Initiative under WHO IVR and WHO/SAGE • Application to Gates • funding started late 2011 !

  11. “Optimizing Immunization Schedules”WHATdoes this mean ? It is NOT about a new schedule • The goal is a processfor decision-making at country or regional level; • this will be continuous,as new vaccines appear and circumstances evolve; • different scheduleswill be appropriate for different epidemiological areas of the world; • incremental gainsof a new schedule need to be substantial to deserve introduction and justify disruption,and; • need to look at all vaccines,not only one,and to consider other factors relevant to well baby care

  12. Strategy • Start vaccine by vaccine, one at a time … • Pneumococcus, Rotavirus, Hib, Hep B, DTP..... • Systematic reviews of vaccine effectiveness and safety • Reviews of epidemiology • Appropriate open presentation of data - 4 “levels” • Development of and interaction with “NITAGS” • National Immunization Technical Advisory Groups • Gates funded “PROVAC” and “SIVAC” initiatives And, on the agenda ... but not yet tackled.... • Procedures for integrating multiple vaccines • “Optimise - Compromise” methods (models ?) • Data and procedures for integrating operational factors and other (non-vaccine) paediatric interventions

  13. Progress: review and provision of data - • PCV pilot, Rota almost done..... Hib next . . . • Rota to be presented to SAGE April 2012 • Commissioning reviews • Proposals requested - trying to involve developing countries • Meetings between reviewers and vaccine experts • very valuable • Note – potential value to all countries • Current duplication by rich countries

  14. Goal - for each vaccine: “Level 1” – 1-3 pages concise summary “Level 2” - 10 – 20 pages detailed summary “Level 3” – full systematic reviews of epidemiology, effectiveness and safety (>> 300 pages) “Level 4” – primary publications

  15. Goal - for each vaccine: “Level 1” – 1-3 pages concise summary “Level 2” - 10 – 20 pages detailed summary “Level 3” – full systematic reviews of epidemiology, effectiveness and safety (>> 300 pages) “Level 4” – primary publications All on website ... with each issue traceable through hyperlinks ....

  16. Examples of presentations for rotavirus vaccines …. Should they be introduced ? If so, by what schedule ? NB SAGE (2009) recommended 1st dose < 15 weeks last dose < 32 weeks (intussusception worry)

  17. Example drawn from systematic review of rotavirus vaccine effectiveness ..... Karla Soares-Weiser, “Enhance Reviews”

  18. Summary from systematic reviews of rotavirus vaccines: effectiveness versus severe rotavirus diarrhoea, by vaccine, number of studies, follow-up duration and WHO mortality strata RV1-1y RV1-2y RV5-1y RV5-2y Hi mortality (Rich) Lo mortality (Poor)

  19. Hospital admissions due to rotavirus gastro-enteritis (eg in Malawi) % of all cases <5 years of age per week of age Age in weeks Colin Sanderson and Andy Clark, LSHTM

  20. Age-specific vaccine coverage and delay data from DHSS surveys for many countries 32 15 6 DTP 1 DTP 2 DTP 3 Colin Sanderson and Andy Clark, LSHTM

  21. Rotavirus gastroenteritis, by age, and implied number of doses of vaccine they “could have received” (eg Vellore India) Colin Sanderson and Andy Clark, LSHTM

  22. Age-specific RVGE – by doses received and implied proportion preventable (eg India) Assuming lower VE Assuming higher VE Colin Sanderson and Andy Clark, LSHTM

  23. D&E Africa, 15+32wk age restrictionsRVGE deaths not prevented by vaccinationRVGE deaths prevented (recipients of 1, 2 and 3 doses) Drop in effectiveness at 52wks due to lower efficacy assumptions 52wks+ Colin Sanderson and Andy Clark, LSHTM

  24. D&E Africa, no age restrictionsRVGE deaths not prevented by vaccinationRVGE deaths prevented (recipients of 1, 2 and 3 doses) Drop in effectiveness at 52wks due to lower efficacy assumptions 52wks+ Colin Sanderson and Andy Clark, LSHTM

  25. D&E Africa, 6-10-14wks on-timeRVGE deaths not prevented by vaccinationRVGE deaths prevented (recipients of 1, 2 and 3 doses) Drop in effectiveness at 52wks due to lower efficacy assumptions 52wks+ Colin Sanderson and Andy Clark, LSHTM

  26. Example - Relationship between estimated number of rotavirus deaths prevented, and intussusceptions attributable to rotavirus vaccine Colin Sanderson and Andy Clark, LSHTM; UmeshParashar and Manish Patel, CDC/Atlanta

  27. We are aware of several problems eg - that vaccines are not randomly distributed – but often “preferentially” to those at lowest risk eg - no “herd immunity” thus the need for explicit qualifications on all impact estimates

  28. Yet to tackle - Combining / compromising multiplevaccines and other well baby interventions Operational implications (suggestions welcome !)

  29. Acknowledgements • WHO-IVR • Ana Maria Henao-Restrepo, Thomas Cherian, Rudi Eggers, Joachim Hombach, OkwoBele • Bill and Melinda Gates Foundation ***** • Walt Orenstein, Matt Hansen • Many experts esp – • SAGE - Jon Abramson, Art Reingold, OyewaleTomori • Pneumococcal vaccines – Keith Klugman, Orin Levine, Kim Mulholland, Anthony Scott, Ron Dagan, Cynthia Whitney, Kate O’Brien, …. • Rotavirus vaccines – UmeshParashar, Manish Patel, Duncan Steele, MathuramSantosham, ShabirMadhi …. • Reviews – Colin Sanderson, Andy Clark, Nicola Low, Pippa Scott, Karla Soares-Weiser, Fiona Russell,…. • SIVAC / PROVAC – KamelSenouci • Presentation – Xavier Bosch • Wise people – Peter Smith, Linda Wharton, Andy Hall, Robin Biellik etc .. N.I.C.E….. Dept of Health … etc

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