Containment of polioviruses in the European Region

WHO

Appropriate containment of eradicated polioviruses (PVs) is a key objective of the Polio Eradication and Endgame Strategic Plan 2013–2018.

This objective aims to ensure that:

  • all poliovirus stocks are safely and securely contained - to minimize the risk of reintroducing these viruses into the population following global interruption of all wild poliovirus (WPV) transmission.

Most facility-associated poliovirus risks can be eliminated through the destruction of WPV and oral polio vaccine/Sabin infectious and potentially infectious materials. However, essential international functions will need to continue in a number of countries, including important research, production of inactivated polio vaccine (IPV), stockpile management of oral polio vaccine (OPV) for use in the event of an outbreak, vaccine quality assurance and diagnostic reagent production.

Ensuring that all WPV infectious and potentially infectious materials are handled and contained safely in certified facilities will allow national and international oversight and ensure that global containment standards can be met.

The majority of vaccine production facilities that handle polioviruses are located in the WHO European Region. The containment of polioviruses is taking place under the oversight and responsibility of national authorities, and WHO/Europe will continue to provide technical support to Member States to prepare for and implement all phases of the containment process.

Containment phases – GAP III

PV containment is taking place in three phases as laid out in the "WHO global action plan to minimize poliovirus facility-associated risk after type-specific eradication of wild polioviruses and sequential cessation of routine OPV use" (GAP III).

Phase I: Global readiness coordination

This phase focuses on the completion of all necessary preparations for containment with the primary emphasis on PV type 2 (PV2) containment measures mediated by the global OPV "switch" from trivalent to bivalent OPV. Early in 2015, WHO/Europe informed all Member States that they should update their inventories of facilities holding any PV and prepare for the destruction or containment of all PV type 2 infectious or potentially infectious materials. To finalize Phase I, all Member States should achieve the following objectives:

  • provide national inventories of all facilities hosting vaccine poliovirus materials;
  • destroy all unneeded PV materials;
  • designate poliovirus essential facilities (PEFs) if further retention of PV is intended;
  • establish a National Authority for Containment (NAC) if a PEF is to be designated;
  • prepare for certification of any designated PEFs.

Phase II: Poliovirus type 2 containment period

The type 2 containment period begins whenever all criteria of preparedness (mentioned above) are met for PV2. It is intended that Phase II would be implemented in two stages. Stage IIa relates to WPV type 2 whereas stage IIb relates to all PV2 and is tightly associated with the global OPV "switch", soon after which the highest risk of reintroduction would be linked with laboratory and manufacturing sites.

In phase II, all essential PV2 materials will be contained in a designated PEF, with its compliance to GAP III certified by an NAC with subsequent international verification. Phase II also implies further preparation activities towards containment of type 1 and type 3 PV, and continues until eradication of all WPVs has been certified.

A Containment Certification Scheme (CCS) was endorsed by the Strategic Advisory Group of Experts on Immunization in October 2017. In addition, to support poliovirus containment activities, a Containment Working Group (CWG) and Containment Advisory Group (CAG) have been established. The CWG and CAG serve as advisory bodies and provide recommendations to the GCC and WHO Director-General, respectively, on implementation of containment requirements. The 1st meeting of the CAG was held on 19-20 June 2017.

Phase III: Final poliovirus containment

Phase III commences when global WPV transmission has not been detected for 3 years, and it is linked with the certification of global WPV eradication.

The Global Polio Eradication Initiative website provides regular updates on global progress toward completion of GAPIII.

Technical assistance in the European Region

WHO/Europe provides technical assistance for GAPIII implementation through training, workshops, country visits and translation and dissemination of guidelines. Regional Office activities since 2015 have included the following:

  • biorisk management training courses in GAPIII implementation for national poliovirus containment coordinators (NPCCs), representatives of polio containment facilities (PEFs) and national authorities for containment (NACs) of Member States that decided to retain type 2 wild polioviruses (WPVs);
  • biorisk management training in GAPIII implementation for laboratories of the European Polio Laboratory Network (EPLN);
  • initial development of a poliovirus containment e-inventory for the European Region;
  • technical assistance to support all EPLN laboratories in switching to a new algorithm of poliovirus isolation in cell-cultures in order to decrease the risk of poliovirus release from facilities;
  • addition of a request for current poliovirus containment progress has been added to the template of the Annual Progress Report on polio eradication activities for 2015.

For more information on containment in the European Region, write to eurorcc@who.int