Summary of new polioviruses this week, cases and positive environmental isolates:

• Pakistan: three WPV1 cases and 28 WPV1-positive environmental samples
• Algeria: two cVDPV2-positive environmental samples
• Cameroon: one cVDPV2 case and one cVDPV2-positive environmental sample
• Chad: four cVDPV2 cases and 3 cVDPV2-positive environmental samples
• Djibouti: one cVDPV2 case and two cVDPV2-positive environmental samples
• Guinea: one cVDPV2-positive environmental sample
• Nigeria: seven cVDPV2 cases