After vaccine-derived poliovirus was found in sewage in Germany, Poland, and Spain in the second half of 2024, there are fears of a potential outbreak in a region that was declared "polio-free" in 2002 (WHO, Euronews, Science.org, European Centre for Disease Prevention and Control - Polio Dashboard). The outcome will be determined using information provided by the EU or government of an EU member state, and the question will close as of the confirmation. The mere acknowledgement of a case being reported alone will not count. A case in a resident will count so long as transmission is reportedly believed to have occurred somewhere in the EU, and whether the virus is "wild" or vaccine-derived is immaterial.

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The question closed "No" with a closing date of 21 June 2025.

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