Rapid Risk Assessment: Outbreak of circulating vaccine-derived poliovirus type 1 in Ukraine, 4 September 2015
This risk assessment was triggered by two cases of paralytic poliomyelitis in children, caused by circulating vaccine-derived poliovirus type 1 (cVDPV1) in Ukraine during June and July 2015. The outbreak of poliomyelitis in Ukraine is not unexpected, given the low polio vaccination uptake and coverage. It represents a threat to public health in Ukraine and the EU/EEA Member States and there is an urgent need to assess the risk of further spread within Ukraine and international spread from Ukraine.
Two cases of paralytic poliomyelitis caused by circulating vaccine-derived poliovirus type 1 (cVDPV1) were confirmed in Ukraine on 28 August 2015. The genetic similarity between the isolates indicates active transmission of cVDPV1. Both cases are from the Zakarpatskaya oblast [region], in south-western Ukraine, bordering Romania, Hungary, Slovakia and Poland.
There is a risk that cVDPV will be imported and transmitted in the EU via a recently infected person shedding the virus and this is assessed in a new ECDC rapid risk assessment. The highest risk of importation and onward transmission is likely to exist in the border areas with Ukraine, particularly in areas where under-vaccinated populations are concentrated on both sides of the border and where there is a high volume of border crossings in both directions.
However, the risk that importation of cVDPV from Ukraine to the EU/EEA would result in a case of paralytic poliomyelitis is low, given the high polio vaccination uptake in EU/EEA Member States.
Member States are also encouraged to review the options proposed by ECDC in the 2013 rapid risk assessment Wild polio virus 1 transmission in Israel – what is the risk to the EU/EEA. Public health authorities, travel medicine clinics and other healthcare providers should advise EU residents who plan to visit Ukraine of the need to be up-to-date with their polio vaccinations.