Polio this week as of 14 February 2018

• New on http://polioeradication.org/: Sudan’s surveillance system under the microscope, and a new addition to our ‘Reaching the Hard-to-Reach’ series, on AFP surveillance in challenging areas of Afghanistan, Syria and Nigeria.

• The 16th International Health Regulations Emergency Committee regarding the international spread of poliovirus recommended that the temporary recommendations to prevent virus spread be extended for a further period of three months.

• Bill and Melinda Gates released their annual letter, answering the 10 tough questions that they hear most often.

• Summary of newly-reported viruses this week: Afghanistan: One wild poliovirus type 1 (WPV1) positive environmental sample reported from Hilmand province. Democratic Republic of the Congo: Three cases of circulating vaccine-derived poliovirus type 2 (cVDPV2) reported, from Tanganyika province. Somalia: Circulation of vaccine-derived poliovirus type 2 (cVDPV2) in the environment has been confirmed in Banadir province, Somalia. See country-specific sections for further details.
  NA: onset of paralysis in most recent case is prior to 2015. Figures exclude non-AFP sources. Lao PDR cVDPV1, all others cVDPV2. cVDPV definition: see document “Reporting and classification of vaccine-derived polioviruses” at [pdf]

Weekly country updates as of 14 February 2018

Afghanistan - No new cases of wild poliovirus type 1 (WPV1) were reported in the past week. The total number of officially reported WPV1 cases in Afghanistan in 2018 remains three.

• The most recent case (by date of onset) was reported in Spinboldak district, Kandahar province, with onset on 6 January 2018.

• One new WPV1 positive environmental sample was reported in the past week, from Nahr-E-Saraj district, Hilmand province, with collection date on 25 September 2017.

• The most recent supplementary immunization days began on 12 February, during which vaccinators are aiming to vaccinate children across 24 provinces. The days are synchronised with a campaign taking place in Pakistan, part of efforts to interrupt transmission of the virus across the shared border.

• Read the latest polio update from Afghanistan to see information on cases, surveillance and vaccination campaigns.

Pakistan - No new cases of wild poliovirus type 1 (WPV1) were reported in the past week. The total number of officially reported WPV1 cases in Pakistan in 2017 remains eight. There are no cases reported in 2018.

• The most recent case (by date of onset) was reported in Zhob district, Balochistan province, with onset on 15 November 2017.

• The most recent supplementary immunization days began on 12 February, during which vaccinators are aiming to vaccinate about 37 million children across the country. The days are synchronised with a campaign taking place in Afghanistan, part of efforts to interrupt transmission of the virus across the shared border.

• Read the latest polio update from Pakistan to see information on cases, surveillance and vaccination campaigns.

Nigeria

• No new cases of wild poliovirus type 1 (WPV1) were reported in the past week. The total number of WPV1 cases for 2016 remains four and no cases have been reported in 2017.

• The most recent case (by date of onset) was reported in Monguno Local Government Area, Borno, with onset on 21 August 2016.

• Nigeria continues to implement an emergency response to the detected WPV1 strain and circulating vaccine-derived poliovirus type 2 (cVDPV2) strains affecting the country (last detected in 2016).

• Post-campaign data from the January supplementary immunization days in Nigeria is being collated. - - The campaign aimed to vaccinate over 26 million children using bOPV.

• The next immunization days are planned for early March.
  As part of the emergency response, subnational surveillance continues to be strengthened.

Lake Chad Basin

• The detection of wild poliovirus type 1 (WPV1) (Borno state, Nigeria in 2016) and circulating vaccine-derived poliovirus type 2 (cVDPV2) (Borno and Sokoto states in 2016) continue to pose a risk to the neighbouring countries of the Lake Chad basin.

• Emergency outbreak response efforts continue across the Lake Chad basin, together with activities to fill subnational surveillance gaps across the region.

• These activities include efforts to vaccinate children at markets, in internally displaced persons camps, and at international borders.

• The next set of supplementary immunization days are planned for early March, and will be synchronized across the whole Lake Chad region.

• Read the latest polio update from the Lake Chad basin to see information on surveillance and vaccination campaigns.

Central Africa

• Three new cases of circulating vaccine-derived poliovirus type 2 (cVDPV2) were reported this week in the Democratic Republic of the Congo. The cases are reported from Tanganyika province, two cases in Ankoro district, with onset of paralysis on 30 November 2017, and 3 December 2017, and one case in Manono district, with onset on 1 December 2017.

• The total number of officially reported cVDPV2 cases in the DRC in 2017 is now 21. There are no cases reported in 2018.

• Outbreak response continues to take place across the country, including use of monovalent oral polio vaccine type 2 (mOPV2) in line with internationally-agreed outbreak response protocols.

• Children living in the districts where the latest cases were reported were last targeted with mOPV2 during December vaccination days.

• Surveillance and immunization activities continue to be strengthened in neighbouring countries.
  Read the latest polio update from the DRC to see information on surveillance and vaccination campaigns.
  Learn more about vaccine-derived polioviruses through this short animation or this ‘Coffee with Polio Experts’ video.

Horn of Africa

• Circulation of vaccine-derived poliovirus type 2 (cVDPV2) has been confirmed in Somalia.

• Three vaccine-derived poliovirus type 2s (VDPV2s) were isolated from two environmental samples collected in Hamarweyn district, Banadir province (Mogadishu), one on 4 January, and one on 11 January 2018. These latest isolates are genetically linked to previously isolated VDPV2s from 2017, collected on 22 October and 2 November from environmental samples collected from Waberi district, Banadir province. In total, four environmental samples (with seven unique virus sequences) positive for cVDPV2 have been collected in Somalia between October 2017, and January 2018.

• No cases of acute flaccid paralysis (AFP) associated with this cVDPV2 have been detected at this time – the viruses were all isolated from environmental samples.

• Surveillance for AFP cases in the area is being strengthened.

• Since detection of the initial isolates in 2017, outbreak response campaigns in line with internationally-agreed guidelines have been implemented, consisting of two large-scale immunization activities (SIAs) in Banadir, Lower Shabelle and Middle Shabelle provinces. A third SIA is planned for March 2018, and further response based on evolving epidemiology and ongoing risk assessment is being evaluated.

• WHO and its partners are continuing to support local public health authorities in conducting field investigations and risk assessments to more clearly assess any potential risk of circulation of the identified cVDPV2, and to continue to support the outbreak response and strengthening of disease surveillance.
  Read our Somalia country page to see information on surveillance and vaccination campaigns.
  Learn more about vaccine-derived polioviruses through this short animation or this ‘Coffee with Polio Experts’ video.

The Middle East

• No new cases of circulating vaccine derived poliovirus type 2 (cVDPV2) were reported this week.

• The most recent case (by date of onset) was reported in Boukamal district, with onset on 21 September 2017.

• The total number of officially reported cVDPV2 cases in Syria in 2017 remains 74. There are no cases reported in 2018.

• Environmental surveillance has been ongoing in Syria since December 2017. So far, results are available for five samples (four from Damascus and one from Deir Ez Zor governorate), with no isolation of VDPV2.

• An inactivated polio vaccine (IPV) immunization round has successfully concluded in Damascus and Hasakah governorates, parts of Aleppo governorate and Jurmana district of rural Damascus as part of the second phase of the outbreak response. A total of 233,518 children aged 2-23 months received IPV, representing 71% of the estimated target. Activities are ongoing in accessible areas of Aleppo governorate.

• A total of 1,456 children under 5 years have received mOPV2 in Hasakah governorate during the IPV vaccination round, as part of special strategies to reach children who were missed by mOPV2 vaccination in January.

• Read the latest polio update from Syria to see information on cases, surveillance and vaccination campaigns.

• Learn more about vaccine-derived polioviruses through this short animation or this ‘Coffee with Polio Experts’ video.