Response to polio outbreak commended

The 24th Meeting of the European Regional Certification Commission for Poliomyelitis Eradication (RCC) took place on 26–27 January 2011 in St Petersburg, Russian Federation. The primary objective was to review the epidemiological situation in the countries infected with imported wild poliovirus type 1 (Kazakhstan, the Russian Federation, Tajikistan and Turkmenistan) and to assess the outbreak-response measures taken to interrupt further transmission in the WHO European Region.

The RCC reviewed this evidence to determine whether the European Region would keep its status as polio free. It reviewed the current situation in six Member States: Kazakhstan, Kyrgyzstan, the Russian Federation, Tajikistan, Turkmenistan and Uzbekistan.

Status of the European Region

The countries where wild poliovirus circulated in 2010, and their neighbours, provided evidence to help the RCC make an independent, expert judgment on the sustainability of the polio-free status of the entire European Region. This evidence focused on the immunity of the population to poliovirus, and the status of certification-standard polio surveillance and laboratory capacity in each country.

The RCC noted that Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan made a strong and adequate response to the extremely large outbreak. Nevertheless, structural and system failures that had enabled an outbreak, such as that in Tajikistan, to occur were long-term issues that still needed to be addressed.

The current success, achieved through supplementary immunization activities (SIAs), was therefore fragile. The central Asian republics (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) and the Russian Federation needed to ensure that all necessary measures were planned and implemented to improve coverage rates for routine immunization with polio vaccine and to strengthen surveillance for acute flaccid paralysis (AFP).

The RCC commended Kazakhstan and the Russian Federation for their timely detection of wild poliovirus importation and immediate response measures. It also advised the two countries to conduct additional SIAs in the affected regions, in accordance with WHO recommendations.

The RCC called for more transparency and cooperation by national authorities in reporting and investigating AFP cases. The failure of one or several countries to share specimens with the poliomyelitis (polio) regional reference laboratory in Moscow, Russian Federation, for confirmation and virus differentiation, could jeopardize the certification status of the entire Region. WHO and health ministries would continue to work with the relevant authorities to resume and/or systematize the shipment of samples in the near future.

Conclusions

In its conclusions, the RCC acknowledged that a large outbreak of wild poliovirus type 1 from northern India had occurred in Tajikistan, with further spread to both neighbouring and distant countries. From the evidence presented, the RCC commended countries’ actions, including the allocation of large amounts of staff and money to stop further poliovirus transmission.

There was no evidence of continued wild poliovirus transmission, but more information was needed about the northern Caucasus, owing to the high risk of transmission in the recent past.

Further reports from the six countries reviewed, due in late June 2011, would put the RCC in a better position to make a recommendation on the certification status of the European Region. All six Member States pledged their readiness to provide the necessary evidence and details for review by the RCC at its next meeting.

Future recommendation on polio certification status

In July 2011, countries may have adequately (a) addressed immunization coverage and implemented needed SIAs; (b) provided detailed information on their polio surveillance systems; and (c) established laboratory arrangements for specimen transport and testing in a timely manner, and the RCC may be satisfied with all their responses. In this case, the RCC may say that:

  • 12 months have passed since wild poliovirus type 1 was imported into the European Region;
  • appropriate, effective actions have been taken, with no sign of continued transmission; and
  • there is thus no need to repeat the process of certifying polio eradication in the Region.

If the RCC doubts that interruption has been successful, however, based on the evidence on the three conditions for countries, it can:

  • delay making a decision on the necessity for recertification of the Region;
  • require recertification only in a subregion; or
  • require recertification of the whole European Region.

It is therefore vital that countries continue their efforts:

  • to prevent further spread, through conducting SIAs and reducing any immunization gaps;
  • to ensure their polio surveillance systems are sensitive to detect any cases of AFP; and
  • to ensure timely specimen testing in a WHO-accredited laboratory.

The RCC held a separate session with the representatives of the six countries affected by the outbreak to discuss their plans for polio activities in 2011, particularly for the next four months. WHO/Europe discussed with Member States the need to coordinate their SIAs to achieve synergy and sustain the momentum for a polio-free Region. Synchronization with countries in the WHO Eastern Mediterranean Region, particularly Afghanistan, was also discussed. These efforts will ensure that wild poliovirus transmission is interrupted in the European Region in 2011.