On Sept. 12, 2024, the Finnish Institute for Health and Welfare (THL) reported that Poliovirus had been found in wastewater monitoring in the Tampere region. The finding was determined to be mutated vaccine-derived poliovirus type 2 (VDPV2). VDPV2 is genetically derived from the original attenuated live virus strain contained in the oral polio vaccine.

The detection of the mutated type 2 poliovirus means that when the samples were collected, there were one or more persons who excreted poliovirus in the area. If a person who is completely or partially unvaccinated comes across said polio virus, they may be infected and, in rare cases, develop symptomatic polio.

Polio is monitored by means of wastewater testing in several European countries. This autumn, mutated type 2 polioviruses have also been found in wastewater monitoring in Spain, Poland and Germany. Testing conducted by the World Health Organisation (WHO) showed that the viruses are genetically linked to the virus strain originally detected in Nigeria, which is still circulating in several African countries. However, no cases of polio have been identified in Europe. 

Polio vaccinations began in Finland in 1957, and Finns are well protected against polio. The last polio case was diagnosed in Finland in 1985. In the same year, live oral polio booster vaccines were offered to the entire population.