Polio viruses discovered in wastewater from other German cities

Dangerous polio

Polio viruses discovered in wastewater from other German cities

Before vaccination was introduced, hundreds of people died of polio every year in Germany. Today polio is considered to be almost eradicated. But now there is a worrying development.

After polio viruses were found in Munich, Bonn, Cologne and Hamburg, the pathogens have now also been detected in samples from other German cities. There were positive tests from sewage treatment plants in Dresden, Düsseldorf and Mainz, as the Robert Koch Institute (RKI) announced. The pathogen was detected in all seven cities that were regularly examined. The tests have been carried out since 2021.

The pathogens that were discovered in mid to late November are not the wild type of polio virus, but rather viruses that originate from the oral vaccination against polio with weakened but live polio pathogens. The weakened vaccine viruses can be excreted and spread by vaccinated people for up to six weeks.

If someone receives the oral vaccination, both the person being vaccinated and their contacts can – in very rare cases – become ill with so-called vaccine polio. Oral vaccination is particularly widespread in Asia and Africa. In this country, only an inactivated polio vaccine (IPV) is vaccinated, which is injected into the muscle.

With the help of the evidence, it cannot be said with certainty whether polioviruses circulate within Germany or whether they were only excreted by people who were infected outside of Germany, explained the RKI. “However, it is conceivable that people in this country can pass on the viruses and – if unvaccinated – some of them will also develop poliomyelitis,” it said.

Any possible local circulation must therefore be stopped quickly in any case. The RKI announced that it had informed the state authorities of all federal states about the further evidence.

The last case of poliomyelitis caused by wild viruses acquired in Germany was recorded in 1990. The last two imported cases were reported to have been registered in 1992.

Poliomyelitis is a highly contagious disease that can cause permanent paralysis in people who are not sufficiently immunized. The RKI advises that existing vaccination gaps should be closed. Medical and public health workers should now be more vigilant for symptoms typical of poliomyelitis.

Polio is also called polio because the pathogen was once so widespread that contact with it usually occurred in childhood. Small children in particular were affected by polio-typical paralysis – usually with permanent damage for their entire life. To date there is no therapy.

According to the RKI, the nationwide vaccination rate is around 90 percent. The Standing Vaccination Commission recommends vaccination at the ages of 2, 4 and 11 months. A booster vaccination is recommended between the ages of 9 and 16. People who have been fully vaccinated against polio are protected against the disease.

The highly contagious virus is usually spread via contaminated hands as a so-called smear infection, and in countries with inadequate hygiene standards also via contaminated water. Polio has been considered almost eradicated worldwide for years due to committed vaccination campaigns.