April 2003 was the first time in Slovakia, when the vaccine derived poliovirus Type 2 was isolated fromwaste water sampled fromthe waste water disposal plant in Vrakun, which collects most waste from Bratislava. The examination in the Regional reference laboratory in Helsinki revealed an almost 15 % divergence from the vaccine strain and genetic identity with the Sabine vaccine strain was 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 not only in persons who excreted genetically modified vaccine strains, but even examples of epidemic occurrence connected with circulation and transfer of VDPV in non-vaccinated or insufficiently vaccinated population. Epidemiologist of the State Faculty Public Health Institute of Bratislava, the capital of Slovakia immediately accepted measures to strengthen surveillance of poliomyelitis at all levels in order to minimize the risk for the origin of paralytic disease in the population. The world-wide activities aimed at eradication of poliomyelitismayeliminate the wild virus fromhuman community as well as fromthe environment. It will be difficult to eradicate poliomyelitis completely before the potentially infectious oral vaccine is substituted with inactivated vaccine.

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