1. Poliovirus Surveillance and Risks to Polio Eradication in India Dr. Hamid Jafari WHO-NPSP

2. Risks to Polio Eradication in India Reintroduction of virus into traditional endemic areas of UP and Bihar –Persistent circulation in areas with recent transmission (West Bengal, Jharkhand) spreading back to endemic areas –Survival of poliovirus in the migrant and mobile communities leading to further spread International importation Persistent undetected transmission in traditional reservoir areas of UP and Bihar

3. Risks to Polio Eradication in India - II Introduction and survival of poliovirus in areas with low population immunity and/or other transmission risk factors outside UP and Bihar Gaps in AFP surveillance or delays in detection of WPV Delayed and/or inadequate response to importation

4. Monthly incidence of WPV1 cases, 2005-2011 High transmission season Any residual WPV transmission is likely to be detected in the coming High Season for Polio

5. Presentation - Key Questions Is the overall sensitivity and timeliness of AFP surveillance adequate? How robust is surveillance in the traditional endemic states of UP and Bihar? What is the quality of surveillance in areas with recent transmission? What is the quality of surveillance in areas where ‘orphan viruses’ have been isolated? What is being done to enhance surveillance for poliovirus?

6. AFP Surveillance Reporting Network 2011* Reporting site N=33,114 *Data as on 10 July 2011 No. of Reporting Sites

7. Non-polio AFP rate 2010 2011* 12.64 8.63 Target: > 2 per 100,000 popn.<15 years Year to date comparison 22973 AFP cases in 2011 vs. 22070 in 2010 Year to date 8.34 *Data as on 10 July 2011

8. % stool collection within 14 days 20102011* 83% 84% Target: > 80% *Data as on 10 July 2011

9. Stool Specimens processed in polio laboratories - India 200620072008 Number of specimen processed 2009 20102011* 65,01191,148100,102109,09883,528 *Data as on 10 July 2011 >55,000 AFP cases investigated in 2010

10. Mean number of days from stool received in laboratory to final result of Wild and Vaccine viruses 200620072008200920102011 *Data as on 10 July 2011

11. Overall sensitivity and timeliness of AFP surveillance The overall sensitivity and timeliness of AFP and laboratory surveillance has continued to improve, however, some areas need further improvements

12. Surveillance in endemic states Bihar & Uttar Pradesh

13. Non-HR blocks Quality indicators, Bihar & UP, 2011 Non HR blocks % adequate stool collection Non-polio AFP rate HR blocks U.P. 16.59 Bihar 28.78 U.P. 82% Bihar 88% *Data as on 10 July 2011 U.P. HR 37.15 Bihar HR 54.4 U.P. HR 83% Bihar 89

14. Surveillance in recent transmission areas West Bengal, Jharkhand & Maharashtra

15. WB & Jharkhand Non-polio AFP rate, 2011* *Data as on 10 July 2011 Jharkhand 7.26 West Bengal 4.35 Year to date No. of AFP cases West Bengal Jharkhand 2010* 2011*

16. WB & Jharkhand % adequate stool collection *Data as on 10 July 2011 Jharkhand 82% West Bengal 87% Jharkhand 82% West Bengal 86% 2010

17. Maharashtra *Data as on 10 July 2011 4.41 Non-polio AFP rate, 2011* 2010* 2011* Year to date No. of AFP cases

18. Maharashtra *Data as on 10 July 2011 83% 2011* % adequate stool collection 2010 84%

19. Surveillance in the traditional endemic states of UP and Bihar: Surveillance in endemic states is of excellent quality with very high case reporting rates in high risk blocks Quality of surveillance in areas with recent transmission AFP case reporting has increased in 2011 compared with 2010, however, a few key districts need further improvements, especially in adequate sample collection

20. Surveillance in areas with ‘orphan’ wild polioviruses

21. Example: Orphan WPV1 detected in UP Transmission detected after a gap of 13 months >1.5% genetic distance

22. Districts with ‘Orphan’ viruses, 2008-2010 WPV1 cases with >1% Genetic distance 28 Orphan WPV1 isolated in 23 districts 1 isolate each in Mumbai & Delhi sewage 4 districts where same genetic strain detected more than once (interval range: 8- 10 months)

23. Quality of surveillance in districts with orphan viruses >1% genetic distance, Jan 2010 – June 2011 Non-polio AFP rate% adequate stool collection *Data as on 10 July 2011

24. Districts with ‘Orphan’ viruses, 2008-2010 10 WPV1 from 8 districts 1 isolate each in Mumbai & Delhi sewage WPV1 cases with >1% Genetic distance WPV1 cases with >1.5% Genetic distance

25. Quality of surveillance in districts with orphan viruses >1.5% genetic distance Non-polio AFP rate *Data as on 10 July 2011

26. 2008 Bihar WPV1 in Saharsa Virus detection intervals: 10 monthsVirus detection intervals: 10 months and 9 months

27. The single 2008 Saharsa isolate ancestor of all subsequent WPV1 strains

28. Enhanced Surveillance in Kosi River Area * data as on 10 July 2011 2011* 2010 200920082007 2008 WPV1 case in Kosi River area No. of AFP cases

29. Surveillance in Districts with ‘Orphan’ WPV Isolates Most Districts with orphan strains have strong surveillance and are unlikely hosts of prolonged undetected transmission Kosi River area of Bihar was the most likely region with undetected transmission until 2009, however, surveillance has been enhanced substantially in this area Many orphan strains likely related to transmission among migrants or in immune populations Isolation of orphan strains in Murshidabad and Nasik districts in 2010 highlight the need for further surveillance improvements in these districts

30. Special Strategies to Enhance Surveillance

31. Role of Migrants in Survival and Spread of Poliovirus Example of most recent WPV1 case

32. Uttar Pradesh (N= 118) Bihar (N= 90) Migration status of WPV1 cases 2007-11 Rest of India (N= 48) Non epidemic UP* (N= 56) *Non epidemic UP excludes Moradabad, JP Nagar, Badaun, Kanshiram Nagar, Bareilly and Rampur districts *Data as on 10 July 2011

33. Pattern of importations of WPV : 2005-11 High risk: > 8 importations and > 5 years with importations Medium risk: : > 5 importations and 3 - 4 years with importations State2005200620072008200920102011TotalRisk Haryana110522 20 High Delhi152542 19 Uttarakhand18412 16 Maharashtra4412 1 12 West Bengal 221 319 Punjab13112 8 Rajasthan 1223 8 Medium Gujarat151 7 Jharkhand21 21 6 Madhya Pradesh 4 1 5 Assam 2 1 3 Low Orissa 12 3 Andhra Pradesh 11 2 Himachal Pradesh 1 1 2 Jammu & Kashmir 1 1 2 Karnataka 1 1

34. Importations in >=4 years Importations in 2-3 years Importation in a year with multiple cases No importation or importation in a year with single case Risk of WPV importation - outside UP & Bihar, 2005-11 *: data as on 12 March 2011 DELHI HARYANAMEWAT UTTARAKHANDHARDWAR ANDHRA PRADESHEAST GODAVARI HARYANAFARIDABAD HARYANAHISAR HARYANAJHAJJAR HARYANAPANCHKULA HARYANAPANIPAT JAMMU & KASHMIRJAMMU JHARKHANDPAKUR MAHARASHTRABEED MAHARASHTRAGR. MUMBAI MAHARASHTRATHANE PUNJABLUDHIANA PUNJABMOGA PUNJABPATIALA RAJASTHANBHARATPUR UTTARAKHANDUDHAMSINGH NAGAR WEST BENGAL24-PARGANAS SOUTH WEST BENGALHOWRA WEST BENGALMURSHIDABAD ASSAMKARIMGANJ HARYANASONEPAT MAHARASHTRANASIK PUNJABHOSHIARPUR UTTARAKHANDDEHARADUN

35. Surveillance in Districts with high risk of importation Non-polio AFP rate, 2011* *Data as on 10 July 2011

36. Enhanced Surveillance Among Migrants Year to date comparisons of reported AFP cases India UP & Bihar 6 States at high risk of importations *Data as on 10 July 2011

37. Non-polio AFP cases in migrants Estimated non-polio AFP rate** amongst migrants 20102011* N=691 N=1588 *Data as on 10 July 2011 ** Estimate based on the number of migrant children vaccinated in SIAs

38. Sewage sampling sites 2010 Sewage sampling initiated 2011 State planned for 2011 States planned for 2012 Further expansion of sites in Delhi & Maharashtra Expansion of Environmental Surveillance in High Importation Risk Areas

39. Surveillance quality assurance Ongoing surveillance reviews 20112010

40. Example: Delhi surveillance review 2010, Key concerns Inadequate informer network in areas with migrants Need for further sensitization of reporting network Number of reporting sites Number of sensitization visits No. of AFP surveillance workshops, 2011 2009 2010 2011* Outcome: Increased number of AFP cases reported *Data as on 10 July 2011 20102011 No. of AFP Cases Reported

41. Special Surveillance Strategies Special efforts ongoing to measure and increase surveillance among migrants Expansion of environmental surveillance guided by risk of importation Ongoing independent surveillance reviews targeted to high risk areas and populations Assessment of local surveillance quality will be a key component of the ongoing risk analyses by states as they develop their polio emergency and response plans

42. Summary Overall, a sensitive surveillance system that meets or exceeds international standards A reliable and efficient laboratory network despite an increasingly heavy workload High AFP reporting rates in endemic states, particularly in high risk blocks Improvements in case reporting in areas with transmission in 2010, however, a few districts need further strengthening Any residual transmission is likely to be detected in the ensuing high season for polio

43. Summary Orphan strains have been detected after an interval of up to 13 months very recently. Migrants have contributed significantly to undetected transmission Focused efforts ongoing to promptly detect transmission in migrant populations Expansion of environmental surveillance will help early detection of virus in high risk areas Most districts with orphan isolates have strong surveillance. Surveillance in Kosi River area has improved substantially.

44. Thank You