The switch

Recent switch of OPV worldwide...

1. - Dr. C.S.N Vittal w itch The

2. - Dr. C.S.N Vittal

3. Replacement of all tOPV with bOPV (containing types 1 and 3 only) in routine immunization and supplemental immunization activities (SIAs) What is the switch?

4. DG of WHO -> comprehensive polio eradication strategy “ Polio Eradication and Endgame Strategic Plan” The first phase of OPV removal Validate - during the two weeks after the switch 2012 2013-18 2016 2 Wks after… WHA declared the completion of poliovirus eradication – a “programmatic emergency for global public health” Removal of all oral polio vaccines (OPVs)- in a phased manner, from both routine programmes and campaigns, to minimize the risk of new polio cases. A switch from the current trivalent oral polio vaccine (tOPV), containing antigens for poliovirus types 1, 2, and 3, to bivalent OPV (bOPV) - Complete disposal of tOPV - Collect and review data and validate switch Brief Introduction …. 2019-2020 : Complete withdrawl of bOPV and OPV routine use

5. 1.Rationale for OPV withdrawal 2.Timelines for switching from tOPV to bOPV 3.Programmatic implications of the switch The Switch

6. 125 Polio Endemic countries 125 Polio Endemic countries to 3 endemic countries Wild Poliovirus Eradication, 1988-2012 1988 2012 Last type 2 polio in the world Last Polio Case in India

7. Data as on 12/02/2014 GLOBAL POLIO CASES Global Polio Cases : Year 2000 = 719 Year 2001 = 483 Year 2002 = 1918 Year 2003 = 784 Year 2004 = 1255 Year 2005 = 1979 Year 2006 = 1998 Year 2007 = 1315 Year 2008 = 1651 Year 2009 = 1604 Year 2010 = 1352 Year 2011 = 650 Year 2012 = 223 Year 2013 = 400 Year 2014 = 11

8. International exportation of poliovirus in 2014 March March February January April June August September October

9. WILD POLIO CASES IN INDIA Data as on 14.02.2014

10. Success in India established strategic & scientific feasibility of poliovirus eradication Poliovirus Type 2 eradication raised concerns about continued use of tOPV

11. Vaccine-derived polio virus (VDPV) 2 VDPV in the immunodeficient person ( iVDPV ) 3 VDPV of ambiguous origin ( aVDPV ) 1 Circulating VDPV ( cVDPV ) – VDPV with evidence of virus circulation in the population causing two or more paralytic cases

12. cVDPV is associated with sustained person-to-person transmission and is circulating in the environment. “Persistent cVDPVs” refer to cVDPVs known to have circulated for more than six months. cVDPVs are extremely rare. - During the last ten years, only 24 cVDPV outbreaks have occurred in 21 countries, resulting in more than 750 cases of paralytic polio. cVDPV

13. Type 2 (478 cases) Type 1 (79 cases) Type 3 (9 cases) Type 2 Type 1 Type 3 >90% VDPV cases are type 2 (40% of Vaccine-associated polio is also type 2) Vaccine-derived polio outbreaks (cVDPVs) 2000-2013

14. ? The Switch

15. The objective of the switch is to stop the emergence of cVDPV2 and VAPP caused by the attenuated type 2 strain of tOPV. What is the objective of the switch ?

16. The purpose of the switch is to eliminate persistent cVDPVs associated with the type 2 serotype and to boost protection against wild poliovirus types 1 and 3 (the switch will not prevent type 1 or type 3 cVDPV). Will the switch from tOPV to bOPV eliminate all cVDPV cases ?

17. Until recently, WPVs caused the majority of paralytic polio cases and attracted the maximum attention. During this time, tOPV is the best strategy for fighting polio. In recent years, great progress has been made in reducing polio transmission, especially with the South East Asia region being certified as polio-free in March 2014. If the last wild poliovirus type 2 (WPV2) was reported in 1999, why is type 2 only now being removed from OPV ?

18. Developments in laboratory capacity have allowed for a better appreciation of the burden caused by cVDPV2s. Only in the last few years have data become available which show that switching to bOPV could aid eradication of WPVs, as bOPV provides better immunogenicity than tOPV to WPV1 and WPV3. If the last wild poliovirus type 2 (WPV2) was reported in 1999, why is type 2 only now being removed from OPV ?

19. Currently, WPV cases reached such low levels that cVDPVs are causing a relatively high proportion of paralytic polio cases. Bivalent OPV had to be available to make the switch to bOPV possible, and bOPV has only become available in the last few years. If the last wild poliovirus type 2 (WPV2) was reported in 1999, why is type 2 only now being removed from OPV ?

20. Increase in the number of individuals susceptible to poliovirus type 2, which In turn will increase the risk of new cVDPV type 2 outbreaks after OPV type 2 cessation… Are there any risks associated with the switch from tOPV to bOPV ?

21. How do we address such eventuality? Wile the objective of the switch is to stop the emergence of cVDPV2 and VAPP caused by the attenuated type 2 strain of tOPV. The planned withdrawal of the type 2 component of tOPV is part of the global polio eradication endgame strategy for 2013-2018.

22. Click to add Title 1 All countries are requested to introduce at least one dose of IPV (containing types 1, 2, and 3) into their routine immunization programmes by the end of 2015 1 Click to add Title 2 To destroy tOPV stocks immediately after the switch 2 Click to add Title 1 Selected countries to conduct SIAs with tOPV in the months leading up to switch 3 Click to add Title 2 Facilitate interruption of transmission with the use of monovalent OPV type 2 in the case of outbreaks 4 Click to add Title 1 Hasten eradication by boosting immunity to poliovirus types 1 and 3 5 How to tackle this risk of possible cVDPV type 2 outbreaks ?

23. ?

24. Importance of IPV introduction Administration of one dose of IPV would boost humoral and mucosal immunity in children already immune from OPV, provide protection against VAPP.

25. January 2013 : 126 OPV-only using countries IPV ONLY (47 countries) IPV/OPV (19 countries) OPV ONLY (126 countries)

26. IPV Introduction status - March 2015 28 Date of slide: 3 March 2015 Introduced to date (82 countries or 42%) Formal commitment to introduce in 2015 ( 106 countries or 55%) Intend to introduce in 2015 ( 4 countries or 2%) (Cook Islands, Fiji, Mauritius, Turkmenistan) Intend to introduce in 2016 (Thailand) Formal commitment to introduce in 2016 (Saint Lucia) Not Available Not applicable 15 introductions 109 commitments/plans to introduce in 2015

27. Polio Eradication Endgame Plan 2013-18 Before end 2015 2016 2019-2020 Ongoing STRENGTHENING of routine immunization services

28. Alignment of Containment & OPV Withdrawal Timelines, (2014-2020) 30 2014 2015 2016 2017 2018 2019 2020 WPV + cVDPV 1 Phase I: Global readiness coordination (until end-2015) Phase II: Global poliovirus type 2 containment period (2016 – 2018) Phase III: Long-term poliovirus containment (as of 2019) Containment of all Sabin Global readiness criteria met Inventory, destruction, preparation for containment Certifica tion 2 OPV2 withdrawal Sabin Destruction, prep. for containment Certification NOW 6 x Regional certification of WPV eradication WPV2/cVDPV2 containment bOPV cessation Sabin2 containment Final containment of all WPV/cVDPV

29. April 2016 Example at country level SAGE: Strategic Advisory Group of Experts on Immunization 2 weeks Switch Window defined globally W1 W2 W3 W4 National Switch Date selected by the country: Any day during that 2 week period Country switches to bOPV Recall & Disposal of tOPV and validation bOPV distribution starts 2 weeks before Last Switch Date No more tOPV use Only bOPV is used globally Global Validation The protocol for the Switch was endorsed by SAGE in October 2014

30. To Summarize

31. History of Polio ????? “…….” Eradication of Polio from the entire world… …………………….. Who had the world’s last case of Poliomyelitis … & so on… History of Polio In Near Future

32. Thank Q Dr. C.S.N.Vittal