On 28 August 2015, the WHO Regional Office for Europe was notified of two confirmed cases of circulating vaccine-derived poliovirus type 1 (cVDPV1) in Ukraine. The two cases have a genetic similarity, which indicates that active transmission of cVDPV1 is ongoing. WHO and UNICEF are supporting the Ministry of Health of Ukraine in conducting an urgent, robust response.
The strain was isolated from two children in Zakarpatskaya oblast, in south-western Ukraine. One child was 4 years old and the other 10 months old at the time of onset of paralysis; neither had been vaccinated against polio.
Circulation of cVDPV occurred because of the low immunization coverage in Ukraine since 2008. In 2014, only 49% of children were fully vaccinated against polio. Currently, the rate of vaccination against polio among children under 1 year old is only 14.1%, because of a shortage of vaccine.
WHO and UNICEF are providing the Ministry of Health with both technical and on-site support in planning and implementing large-scale supplementary immunization activities with oral polio vaccine (OPV) to rapidly stop circulation of the virus. OPV is the most effective vaccine for stopping the spread of poliovirus and ensuring collective immunity.
WHO recommends that all countries, in particular those from which there is frequent travel and contacts with polio-affected countries and areas, strengthen surveillance for cases of acute flaccid paralysis and maintain high routine immunization coverage. All travellers to polio-affected areas should be fully vaccinated against polio.