Berlin data indicate a massive Corona wave
In the German capital, something is brewing together: In sewage treatment plants, researchers are registering a notable increase in measured virus levels in the middle of summer. The responsible health and social affairs department (Lageso) confirms this. "Currently, we are seeing a SARS-CoV-2 wave with an increased excretion of SARS-CoV-2 RNA", confirmed a spokesperson Daniel Sagebiel in response to an inquiry.
The unusual accumulation of summer infections in Berlin is not only due to harmless sore throat viruses. Routine measurements in the sewage indicate a significant increase in Corona infections in the catchment area of the German capital. The measured virus loads are rising steeply at all three Berlin sewage treatment plants - Ruhleben in the northwest, Schöneberg in the north, and Wassmannsdorf in the south of the city. Previous statements suggest that this covers the sewage of around 84 percent of the Berlin population.
"Coronaviruses enter the sewage system, for example, during toothbrushing through saliva or particularly through excretions from the digestive tract", explains Lageso doctor Sagebiel. In the case of an infection, Coronaviruses multiply unnoticed in the human body. This happens several days before the first symptoms appear. The sewage samples can therefore provide indications of possible infection waves in the population long before other indicators start.
The sewage screening does not allow statements about the individual disease course or about a possible increase in severe Covid-19 cases. Therefore, doctors also keep an eye on reports from doctors' offices and hospitals. So far, there are no indications of an increase in severe Corona infections. However, the other available indicators for the Corona situation - such as Covid-19 cases on intensive care units - usually follow the development several weeks later.
Nationwide, the calculated number of respiratory diseases decreased slightly recently - however, the Robert Koch Institute (RKI) referred to possible influences on the consultation behavior of the population due to the beginning of the holidays in several federal states. Sewage treatment plants in individual other German metropolises, such as Düsseldorf, also show a noticeable increase in virus loads - but not in the Berlin dimensions.
The sewage monitoring offers virologists, doctors, and epidemiologists significant advantages over other early warning systems: The sewage samples allow a much more comprehensive and faster overview of the current infection situation. "Fewest people go to testing every day", summarizes Sagebiel, "but everyone goes to the toilet every day".
In a single sewage sample, excretions from hundreds of thousands of people are contained. As a early warning indicator, the sewage probing is not only much more convenient, but also "significantly cheaper than the assessment of each individual person using PCR tests".
"Besides the measurable virus amount, involved researchers also focus on the type of contained agents. In the lab, found virus remnants are sequenced. In this way, it is possible to determine the dominant virus variant and also recognize new mutated strains early on.
Coronation Mutations in Focus
"The current increase in the substance since mid-April goes hand in hand with a large number of sublineage variability," it is said from Berlin. "Currently, in the Corona Virus genome, a multitude of various combinations of mutations are arising, which are then classified as different sublineages." In Berlin's sewage, this is currently mainly the subtypes JN.1.18 and KP.3. The trend, however, is still unclear.
Additionally, in addition to sewage monitoring at the three largest Berlin clarification plants, an "automatic sample collector" takes a 24-hour mixed sample from the Berlin Brandenburg Airport BER's sewage system once a week. The contained virus remnants are also sequenced. Virologists want to keep the influence of tourist streams in mind with this.
The measured virus amounts in the sewage are no longer infectious. "The Coronavirus is very sensitive to environmental influences and cleaning agents due to its shell, so there are no intact Coronaviruses in the sewage anymore, but only RNA fragments of the viruses."
The increase in Coronaviruses detected in Berlin's sewage treatment plants could indicate a surge in Sars-Cov-2 infections, as confirmed by Lageso's spokesperson Daniel Sagebiel. The Corona vaccine is not mentioned directly in the text, but it's important to note that vaccination campaigns are ongoing globally, including in Germany, as a key strategy to combat the spread of Sars-Cov-2 and other Coronaviruses. In Berlin schools, there have been discussions about possible measures to ensure safe education amidst the ongoing Coronavirus infections diseases situation.
