The recent detection of wild-type polio virus 1 (WPV1) in sewage and asymptomatic carriers in Israel raises new questions on the potential for the importation and re-establishment of WPV in EU/EEA countries. In the new rapid risk assessment, ECDC concludes that there is the possibility that poliovirus may be imported and re-established in the EU/EEA. Furthermore, based on the limited information on existing surveillance systems, there is a risk that poliovirus circulation will go undetected if it is imported.
The highest level of risk is posed by the proximity of clustered un- or under-immunised population groups to large populations vaccinated using inactivated polio vaccine (IPV)-only schemes. Sub-optimal hygiene and crowded living conditions may also play a role in facilitating the spread of infection.
Vaccination coverage levels in the EU/EEA can be considered satisfactory as a whole (>90% for three doses of either IPV or OPV) and can explain the absence of WPV circulation in the region so far.
However, there are also pockets of the population that are un- or under-immunised who are at greater risk of infection and disease. It is estimated that 12 million people in the EU under the age of 29 have not been vaccinated or completed the recommended national primary vaccination schedule for polio.
Unvaccinated pockets need to be identified, and targeted actions to increase vaccination coverage in these populations need to be addressed urgently.
“If WPV can re-emerge in Israel, with a comparable healthcare system to much of the EU and polio vaccination coverage, then we must accept that there is risk that it could re-emerge in the EU/EEA.
"The way to prevent this is not easy but it is known: prevent; detect; respond. Additional efforts have to be made to have at least a national average of 90% vaccination coverage rate and un- and under vaccinated groups need to be identified and targeted.
"Surveillance systems need to be in place and working well to detect poliovirus early. And finally, Member States need to have national response plans in place in the event of an outbreak.
"This is exactly what the Israeli public health authorities have done to prevent the spread of poliovirus.” said ECDC Director, Dr Marc Sprenger.