Twelfth meeting of the Emergency Committee under the International Health Regulations (2015) regarding the international spread of poliovirus

Published: February 24, 2017

The twelfth meeting of the Emergency Committee (EC) under the International Health Regulations (2005) (IHR) regarding the international spread of poliovirus was held on 7th February 2017.

The Emergency Committee reviewed the data on wild poliovirus (WPV1) and circulating vaccine-derived polioviruses (cVDPV).

Conclusion
The international spread of poliovirus remains a Public Health Emergency of International Concern (PHEIC), and recommended the extension of the Temporary Recommendations for a further three months. The Committee considered the following factors in reaching this conclusion:

• The outbreak of WPV1 and cVDPV in Nigeria highlighting that there are high-risk areas where surveillance is compromised by inaccessibility, resulting in ongoing circulation of WPV for several years without detection. The risk of transmission in the Lake Chad sub-region appears high.
• The continued international spread of WPV1 between Pakistan and Afghanistan.
• The persistent, wide geographical distribution of positive WPV1 in environmental samples and AFP cases in Pakistan, while acknowledging the intensification of environmental surveillance inevitably increasing detection rates.
• The current special and extraordinary context of being closer to polio eradication than ever before in history, with the lowest number of WPV1 cases ever recorded occurring in 2016.
• The risk and consequent costs of failure to eradicate globally one of the world’s most serious vaccine preventable diseases. Even though global transmission has fallen dramatically and with it the likelihood of international spread, the consequences and impact of international spread should it occur would be grave.
• The possibility of global complacency developing as the numbers of polio cases continues to fall and eradication becomes a possibility.
• The serious consequences of further international spread for the increasing number of countries in which immunisation systems have been weakened or disrupted by conflict and complex emergencies. Populations in these fragile states are vulnerable to outbreaks of polio. Outbreaks in fragile states are exceedingly difficult to control and threaten the completion of global polio eradication during its end stage.
• The continued necessity for a coordinated international response to improve immunisation and surveillance for WPV1, to stop international spread and reduce the risk of new spread.
• The importance of a regional approach and strong cross¬-border cooperation, as much international spread of polio occurs over land borders, while also recognizing that the risk of distant international spread remains from zones with active poliovirus transmission.
• Additionally with respect to cVDPV:
  • cVDPVs also pose a risk for international spread, which without an urgent response with appropriate measures threatens vulnerable populations as noted above;
  • The ongoing circulation of cVDPV2 in Nigeria and Pakistan, demonstrates significant gaps in population immunity at a critical time in the polio endgame;
  • The ongoing urgency to prevent type 2 cVDPVs following the globally synchronized withdrawal of the type 2 component of the oral poliovirus vaccine in April 2016;
  • The ongoing challenges of improving routine immunization in areas affected by insecurity and other emergencies, including the post Ebola context;
  • The global shortage of IPV which poses an additional threat from cVDPVs.

Links
http://www.who.int/mediacentre/news/statements/2017/poliovirus-twelfth-ec/en/
http://polioeradication.org/polio-today/polio-now/public-health-emergency-status/