Polio Endgame Strategy in India Considerations and Way Forward WHO-India, NPSP 15 March 2012
Outline of the presentation Background/Context Considerations Possible Way forward
Context No WPV2 in India since 1999 tOPV used in RI and during NIDs bOPV used in most SNIDs since Jan 2010 Areas and populations with low routine immunization coverage All cVDPVs in India due to type 2 in setting of low immunity to type 2
Last wild poliovirus cases by type, India WPV2 24/10/1999 Aligarh (UP) WPV1 13/01/2011 Howrah (WB) WPV3 22/10/2010 Pakur (JH)
Current pattern of vaccine use-India tOPV –EPI schedule: 6,10,14 wks Birth dose for institutional births –SIAs: 2 NIDs with tOPV each year bOPV –Introduced in Jan 2010 –Used extensively during SNIDs in high risk states/ areas 70.4% < >= 80 Assessed tOPV3 coverage by CES 2009
cVDPV cases, India cVDPV cases detected in % due to type 2 District Type Badaun300 Bulandshahar200 Ghaziabad010 Meerut200 Moradabad200 Pilibhit400 Shahjahanpur210 Total1520
Low seroprevalence against poliovirus type 2 Results from different serosurveys Moradabad Nov 2007 (N=121) AFP cases UP Nov 08 – mid 09 (169) Moradabad May 2009 (N=534) UP & Bihar Aug 2010 (N=1280) UP & Bihar Aug 2011 (N=1246) Age 6-7 mo6-11 mo6-7 mo 6-11 mo Type 1 78% 96.5% 99%98%98.5% Type 2 56% 33.7% 75%65%85% Type 3 69% 42.6% 49%77%88.2%
cVDPV type 2 Uttar Pradesh Number of cases c VDPV type 2 tOPV < 25% 25 to 50% 50 to 75% >= 75% tOPV sNID tOPV NID tOPV sNID tOPV NID Evaluated OPV3 coverage by district – DLHS 3 ( ) and cVDPVs
iVDPV & aVDPV cases, India 2009 to 2012* *: data as on 10 March 2012 iVDPVaVDPV ambiguous VDPV (aVDPV): origin uncertain e.g. single isolate from single AFP case, non-immunodeficient person
Managing the risk of VDPVs
tOPV-bOPV switch in India? Considerations Pre-switch increase in type 2 immunity Rapidly improve routine immunization coverage Use of IPV in conjunction with bOPV/tOPV to reduce risk of emergence and consequences of cVDPV Availability of vaccines –IPV availability for use in routine immunization –bOPV availability for routine immunization and SIAs Management of post-switch risks of type 2 VDPVs cVDPV type 2 circulation stopped everywhere & switch synchronised globally
Pre-switch boosting of type 2 immunity Switch soon after tOPV NIDs Improve RI, particularly DTP3 and OPV3 coverage Adding a dose of IPV in RI for infants prior to switch
IPV introduction Benefit – impact on RI ? Timing/Age/Doses/Route – follow global SAGE recs ? Frequency: 2 doses in known cVDPV risk areas? Modelling and Research in the India context may help optimise strategy for India
bOPV availability Licensure and pre-qualification of additional manufacturers to meet requirements of India pre and post-switch bOPV assessment study to support licensure of additional manufacturers
Post-switch VDPV type 2 risk management Heightened surveillance to detect post- switch Sabin type 2 (not just VDPV type 2!) Stockpile/ Capacity to produce mOPV2 at short notice Certification standard surveillance to continue beyond certification
NID 0 JanMarMayJulSepNovJanMarMayJulSepNovJanMarMayJulSepNovJanMarMay Polio Endgame Strategy-India, Possible Way Forward Last WPV case Polio certification IPV NID tOPV NID Post- switch Sabin type 2 risk mgt. tOPV- bOPV switch NID Certification standard surveillance, improved RI coverage PQ/ licensing, stockpile Modelling, Research, Development
Conclusions India can be in a position to move ahead with polio endgame strategy Careful planning and consideration of risks required before implementation Earliest possible timing for tOPV-bOPV switch: Qtr Lessons from tOPV-bOPV switch significant for subsequent withdrawal of all OPV from programme