Polio, also known as infantile paralysis, was once one of the most feared diseases worldwide. Before the introduction of vaccines, wild polioviruses circulated worldwide. While many infections caused only mild symptoms, the virus could sometimes lead to severe paralysis or even death. Thanks to effective vaccination, polio is extremely rare today, but continued awareness and immunization remain essential to keep it that way.

Since the end of November 2024, traces of polioviruses have been found in wastewater in several German cities, including Munich, Bonn, Cologne, Hamburg, and later in Dresden, Mainz, and Stuttgart. These are known as vaccine-derived polioviruses, which originally come from attenuated oral vaccines.