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

• Afghanistan: one wild poliovirus type 1 (WPV1) case and 10 WPV1-positive environmental samples
• Pakistan: seven WPV1 cases and one WPV1-positive environmental sample
• Chad: three circulating vaccine-derived poliovirus type 2 (cVDPV2) cases and two cVDPV2-positive environmental samples
• Djibouti: one cVDPV2-positive environmental sample
• Niger: once cVDPV2 case and one cVDPV2-positive environmental sample
• Nigeria: five cVDPV2 cases