European countries to participate in global polio vaccine switch
Every country in the world that is currently using trivalent oral polio vaccine (OPV) (containing all three serotypes of poliovirus) will permanently withdraw this vaccine from their immunization programmes and activities on one appointed day in the 2-week period 17 April –1 May 2016. These countries will replace the vaccine with bivalent OPV – containing only types 1 and 3 – or move to an immunization schedule with only the inactivated form of polio vaccine (IPV). 19 countries in the European Region will participate in this unprecedented, globally synchronized vaccine "switch".
To fully eradicate polio, all OPV will be phased out entirely; and the process is starting with the OPV switch in April 2016. Wild poliovirus type 2 has not been circulating since 1999 and was declared eradicated in September 2015. Removal of this eradicated serotype from the vaccine will further reduce the rare risk that a type 2 vaccine-derived poliovirus will emerge. The type 2 component of trivalent OPV also interferes with the immune response to poliovirus types 1 and 3.
In addition, at least one dose of IPV is being added to boost protection against all three types of poliovirus.
Criteria for the switch
Before the switch can take place, several criteria must be met. In addition to the official declaration that wild poliovirus type 2 has been eradicated globally, initial steps must have been taken to ensure global laboratory containment of poliovirus type 2. Moreover, each country must have:
- introduced (or have a planned date to introduce) at least 1 dose of inactivated polio vaccine (IPV) into their routine schedules;
- licensed bivalent OPV and have it available for routine immunization; and
- put in place surveillance and response protocols for possible type 2 poliovirus outbreaks.
Preparing for the switch
Over the past 2 years, WHO/Europe has been supporting countries in preparing for the switch through workshops, country visits, translation and dissemination of global guidelines, external fund-raising for switch implementation, field testing and acceptance studies.
On 30–31 March 2016, a workshop was held for all countries that use OPV in their regular immunization schedules:
- to discuss country preparedness;
- to review plans for the disposal of trivalent OPV after the switch and for monitoring the process;
- to analyse threats to the switch plans and to discuss solutions;
- to give countries an opportunity to discuss other issues related to the switch and learn from each other; and
- to discuss possible last-minute support required for the switch.
The outcome of the meeting demonstrated that the countries in the European Region are on track in preparing for the switch.
Activities on the day of the switch
All health facilities in every country will stop using trivalent OPV on one selected day within the 2-week switch period. Any remaining trivalent OPV stock must be collected and destroyed according to national guidance.
The countries in the WHO European Region that will switch to bivalent OPV are Albania, Armenia, Azerbaijan, Bosnia and Herzegovina, Georgia, Kazakhstan, Kyrgyzstan, Montenegro, the Republic of Moldova, the Russian Federation, Serbia, Tajikistan, the former Yugoslav Republic of Macedonia, Turkey, Turkmenistan, Ukraine and Uzbekistan. Belarus and Poland will move to an IPV-only schedule.