Isolation of Highly Divergent VaccinePoliovirus in Slovakia

Overview

April 2003 was the first time in Slovakia, when the vaccine derived poliovirus Type 2 was isolatedfromwaste water sampled fromthe waste water disposal plant in Vrakun, which collects most wastefrom Bratislava. The examination in the Regional reference laboratory in Helsinki revealed analmost 15 % divergence from the vaccine strain and genetic identity with the Sabine vaccine strainwas only 86.6 %. Various cases of paralytic poliomyelitis have been published in world literature,caused by mutants = vaccine derived polioviruses (VDPV). Sporadic diseases were described notonly in persons who excreted genetically modified vaccine strains, but even examples of epidemicoccurrence connected with circulation and transfer of VDPV in non-vaccinated or insufficientlyvaccinated population. Epidemiologist of the State Faculty Public Health Institute of Bratislava, thecapital of Slovakia immediately accepted measures to strengthen surveillance of poliomyelitis at alllevels in order to minimize the risk for the origin of paralytic disease in the population. Theworld-wide activities aimed at eradication of poliomyelitismayeliminate the wild virus fromhumancommunity as well as fromthe environment. It will be difficult to eradicate poliomyelitis completelybefore the potentially infectious oral vaccine is substituted with inactivated vaccine.

Key words:
VDPV – poliomyelitis – surveillance of poliomyelitis – OPV – IPV.