Sustaining Polio Eradication IEAG March 2012 The experience of polio-free countries with importations of WPV: Implications for India

Importations will happen Since 2000, 44 countries that had been polio free have suffered from one or more importations of wild poliovirus Lesson 1

Data at WHO HQ as of 24 January 2011 Routes of travel associated with polio cases, (10 years) 341* 1 * 341 confirmed cases ( ), however 540 AFP cases are pending classification in the Congo from the 2010 outbreak. ** 5 WPV cases into Zambia in from indigenous transmission in Angola Air / Sea routes Road Viral origin: India Viral origin: Nigeria <100 cases 100  300 cases >300 cases Further spread 1 5**

The chances of importation - exposure to WPV Population immunity - the likelihood that imported virus will spread The main factors affecting the chances of an outbreak

Speed of detection Speed of response Population immunity The main factors affecting the size & duration of an outbreak

Prior exporter – what goes out can come back…. Bordering / in proximity to 2 endemic countries Significant international population movement India has multiple risk factors for exposure to WPV

Maintain population immunity Countries with better baseline immunity have smaller outbreaks and stop them more quickly Lesson 2

Last indigenous case: 1997 Outbreak: 2005 Size of outbreak: 303 cases Duration of outbreak: 13 months Indonesia

Last indigenous case: 2000 Outbreak: 2006 Size of outbreak: 18 cases Duration of outbreak: 8 months Bangladesh

The difference immunity makes: % Under Immunized Non-polio AFP Cases (< 5 Yrs) the year of the outbreak Indonesia had a far larger immunity gap in 2005 than Bangladesh in 2006 Indonesia had a much larger outbreak and took longer to stop it

Maintaining immunity: differences in SIA schedules Indonesia conducted only 2 national rounds in the four years prior to the outbreak; B'desh conducted 8.

Maintain surveillance quality Countries with better surveillance are more likely to find WPV / cVDPV faster Lesson 3

The difference surveillance makes: Non-polio AFP rates the year before the outbreak Indonesia had a less sensitive surveillance system in 2004 than Bangladesh in 2005 Indonesia took longer to detect and respond to the outbreak

Indonesia outbreak: epidemic curve and SIAs Data as of 24 July Mop-up 3 provinces 31 May Mop-ups 3 provinces 28 Jun NID 30 Aug NID 27 Sep NID 30 Nov SNID 30 Jan NID 22 Feb NID 12 Apr WPV1 positive contact in Aceh Tenggara 13 Apr 2006 WPV1 case in Aceh Tenggara 26 Feb Late detection & nearly 3 months onset to response

Respond fast Countries responding more quickly have shorter and smaller outbreaks Lesson 4

Last indigenous case: 1994 Outbreak: 2011 Size of outbreak: 21 cases Duration of outbreak: 3.5 months China

Polio outbreak China - key timeline 6 July: Onset of first case 24 August: Preliminary lab result of WPV 26 August: Level 2 public health emergency announced; Notification thru IHR 27 August: Vice Minister Health, China flies to Xinjiang Video conference with all prefectures and counties 28 August: >90 China CDC experts from around country arrive 30 August: Emergency plan launched 1 September: TV promotion campaign begins 2 September: 5m doses of tOPV arrive by China Air Force cargo plane 3 September: Training of > 1000 staff for SIA and surveillance 7 September: Video conference with 2300 political leaders 8 September: Start of 1 st SIA covering >4 million children Launched in Hotan prefecture by Minister of Health, China 15 days

Impact of speed of response Median duration of outbreaks & # of rounds to control

Be flexible in response Wider target age groups and short interval rounds may impact on size and duration of outbreaks Lesson 5

Last indigenous case: 1994 Outbreak: 2010 Size of outbreak: 458 cases Duration of outbreak: 6 months Tajikistan

Flexible response, Tajikistan 2010 SIA Round 1 mOPV1 (99.4%) SIA Round 2 mOPV1 (99.4%) SIA Round 3 mOPV1 (98.8%) SIA Round 4 mOPV1 (99.3%) Mop-up Sep mOPV 34 districts (98-100%) SIA Round 5 tOPV SIA Round 6 tOPV 4 x Short interval rounds 3 rd & 4 th rounds expanded target age group

Impact of age group immunized Median duration of outbreaks & # of rounds to control

Assess and mitigate risks Identifying risks allows for actions to minimize it Lesson 5

Subnational polio risk assessment Western Pacific Region, 2011* Low risk Medium risk High risk LEGEND: * Source: country progress reports submitted to RCC17 (Nov 2011)

Historically, the risk of a significant outbreak in any country following cessation of indigenous transmission has increased over time Why? –Population immunity wanes –Surveillance quality deteriorates –Experience is lost Conclusion: risks for a polio free India

Eradicate all circulating poliovirus globally and certify eradication Until then: - Maintain high population immunity (routine plus SIAs) - Maintain high quality surveillance & capacity to respond Conclusion: how can India be protected?