Polio This Week | GPEI | Most Recent News | Countries
Polio this week

Containment Advisory Group Clarifies Containment Requirements for Polio Virus-Like Particles (VLP)

At its recent June 2026 meeting, the Containment Advisory Group (CAG) reviewed the application of poliovirus containment requirements to Polio Virus-Like Particles (VLPs) and related laboratory activities. Following expert deliberations, the CAG concluded that polio VLPs, as non-infectious and non-replicating particles that do not contain poliovirus RNA, are not subject to poliovirus containment requirements. The CAG also clarified that containment requirements apply only when manufacturers or laboratories perform neutralization testing using live poliovirus, in accordance with the containment measures appropriate to the type of virus handled. Testing based on pseudoviruses does not fall within the scope of containment requirements. This clarification provides important guidance to vaccine developers, manufacturers, laboratories, and National Authorities for Containment, supporting consistent implementation of the Global Action Plan for Poliovirus Containment while fostering innovation in polio vaccine research and development.

Summary of new polioviruses this week

  • Afghanistan :  four WPV1 cases
  • Pakistan:  three WPV1-positive environmental samples
  • DR Congo :  five cVDPV2 cases
  • Madagascar :  one cVDPV1-positive environmental sample
  • Nigeria :  one cVDPV2 case
  • Somalia :  one cVDPV2-positive environmental sample
Country updates as of 09 September 2026

More information on the countries that have reported cases and/or environmental samples this week.

  • Four WPV1 cases were reported this week, from Farah, Nuristan, Kunar and Hilmand, with onsets of paralysis in July and August. The total number of cases in 2026 is 23 (most recent case: 2 August 2026). The total number of cases in 2025 is 21.
  • No WPV1-positive environmental samples were reported this week (most recent positive environmental sample: 27 July 2026).

  • No WPV1 cases were reported this week (most recent case: 7 April 2026). The total number of cases in 2026 is three. The total number of cases in 2025 is 31.
  • Three WPV1-positive environmental samples were reported this week, collected in August from Sindh and Khyber Pakhtunkhwa (most recent positive environmental sample: 11 August 2026).

  • Five cVDPV2 cases were reported this week from Haut Lomami, with onset of paralysis in May and July 2026 (most recent case: 27 July 2026). The number of cVDPV2 cases in 2026 is 50. The number of cVDPV2 cases in 2025 is seven.
  • No cVDPV2-positive environmental samples were reported this week (most recent positive environmental sample: 14 May 2026).
  • No cVDPV1 cases were reported this week. The number of cVDPV1 cases from 2025 is one (onset of paralysis: 25 June 2025).

  • No cVDPV1 cases were reported this week. There are two cases reported in 2026 (most recent case: 13 May 2026). 
  • One cVDPV1-positive environmental sample was reported this week, from Atsimo Andrefana, collected on 6 July 2026 (most recent positive environmental sample).

  • One cVDPV2 case was reported this week, from Kano, with onset of paralysis on 18 August 2026 (most recent case). The total number of cVDPV2 cases reported in 2026 is 35. The total number of cVDPV2 cases reported in 2025 is 66. 
  • No cVDPV2-positive environmental sample was reported this week (most recent positive environmental sample:  22 July 2026).
  • No cVDPV3 cases were reported this week. The total number of cVDPV3 cases in 2026 is eleven (most recent case:  25 July 2026). The total number of cVDPV3 cases in 2025 is eight.
  • No cVDPV3-positive environmental samples were reported this week (most recent positive environmental sample: 16 July 2026).

  • No cVDPV2 cases were reported this week (most recent case: 22 June 2026). There are six cases reported in 2026. Two cases were reported in 2025. 
  • One cVDPV2-positive environmental sample was reported this week, from Banadir, collected on 3 August 2026 (most recent positive environmental sample).