Statisticians are currently largely flying blind with regard to corona infections. A look into the sewage might help. However, the process is still in its infancy in MV.
Greifswald/Rostock (dpa/mv) - The Greifswald bioinformatician Lars Kaderali has spoken out in favor of expanding wastewater tests to include Corona. "I would find it useful because it can be operated with relatively little effort," said Kaderali, who is a member of the federal government's Corona Expert Council, of the German Press Agency. Corresponding studies would give good indicators, especially for the course of the infection process. The German medical officers had recently spoken out in favor of an expansion.
In the north-east, only Rostock has so far examined sewage for corona. The basis is stool excretions in which the virus can be detected. This, in turn, can be used to track the distribution in a region. According to experts such as Kaderali, numbers on the infection process based on PCR tests are currently hardly reliable, since by far not all infected people can be tested.
For Germany, Kaderali assumes that there are up to four times as many corona infections as officially registered. This can be roughly estimated by comparing wastewater data and registered infections from the current wave with data from previous waves. However, the corresponding wastewater data is not yet available specifically for the north-east.
According to Nordwasser GmbH, around 35 samples have been sent from Rostock to an external laboratory for analysis since mid-March. A reliable evaluation with a view to the pandemic is not yet possible. The data would be used to develop a model to be used throughout Germany as an early warning system. Influencing factors such as the amount of rain also played a role. 20 sewage treatment plant operators are taking part in the project.
According to Kaderali, one advantage of wastewater analyzes is that the infection process can be seen even more quickly than in the data reported by the Robert Koch Institute (RKI). The reason is the delay in reporting by the health authorities.
The Schwerin Ministry of Health came to the conclusion: "The wastewater analysis could be a good, additional tool for pandemic assessment in the future." Germany is still in the test phase. According to their own statements, they want to wait for the results of the model tests at the city and community day in MV. If it works well, the approach could also be used for other pathogens beyond the corona virus.
In numerous countries, wastewater is examined for Sars-CoV-2 in smaller projects or in the course of larger surveys. In neighboring countries such as Austria and the Netherlands, corona dashboards on the Internet show the results.
For Kaderali, there is a better way to monitor the pandemic than just sewage tests. "You could do a representative sample for that." For example, you could test the same 100,000 people across Germany every two weeks. "Then you have a very good representative picture of the situation." However, such a method could not be established until next year at the earliest, said the scientist, referring to RKI information.