Researchers from the University of Chemical Technology have been monitoring the amount of coronavirus in wastewater for a long time, in cooperation with Prague Waterworks and Sewerage. According to them, the number of copies of viral RNA captured now clearly shows that the number of people infected in Prague in the second half of September 2021 is close to the numbers recorded in mid-April this year.
At that time, approximately 5,000 people with a laboratory-proven covid-19 were registered in the capital. This corresponds to approximately 400 cases per 100,000 inhabitants.
However, the current official data are completely different – as of September 27, official statistics in Prague show 1,173 infected people. The occurrence of the virus in wastewater thus indicates a several times higher number of actually infected.
“Estimates are, of course, obligatorily limited by the error, according to which our data in Prague of people infected with covid-19 are at least three to five thousand,” says associate professor Jan Bartáček from the Institute of Water Technology and the Environment of the ICT Prague.
According to university experts, the method used to monitor the covid-19 epidemic is based on the fact that most of those infected massively excrete virus debris in the stool. In the same way, viral RNA enters wastewater.
“During the whole epidemic, it was confirmed that the amount of viral RNA in wastewater clearly correlates with the ongoing epidemic, thanks to which it is possible to estimate the number of infected in the population based on these data,” says Associate Professor Bartáček.
We have until this summer, the data from wastewater roughly correspond to the beginnings of those infected reported The Ministry of Health, during September, seizures in wastewater are rising much faster than the number of positive clinical trials.
High seizures were repeatedly popular in September in the main tributary to the Prague Central Wastewater Treatment Plant, but also in many smaller sampled localities, such as student dormitories, some places in the center of Prague, around the bus terminal and others.
Viral RNA, on the other hand, has not yet been captured in peace monitoring on the basis of the usual residential localities, such as Prague housing estates or residential buildings.
“From the results, we conclude that the number of infected people who excrete the virus into wastewater is really rising sharply. The discrepancy with the official numbers of infected may result from the fact that there are a large number of people in Prague with a less serious course of the disease who do not get tested. This can be done, for example, with high vaccination coverage or population penetration, “adds Bartáček.
He points out that, together with colleagues from the Institute of Microbiology and Biochemistry and the Institute of Biotechnology, they consider it important that, thanks to this state institution, they find it seriously concerned and urgently increase testing intensity so that official statistics better reflect the actual course of the epidemic.
Infection among young people
Also official statistics, which now coronavirus in Prague is spreading fast. However, the data show a more moderate spread than that reported by the ICT.
In the last seven days, tests have confirmed 734 new cases, 15 percent more than a week earlier. During the whole of September, there were 2,616 confirmed cases of the disease in the metropolis. It was a thousand more than in August, but at the same time a quarter of last September. Per 100,000 inhabitants, there are 55 new cases of infection in the capital in the last seven days.
“Of the individual age categories, we currently have the most affected category of children of school age six to 11 years, the second most affected category is 12 to 15 years. There is the highest proportion of patients, “last week for the List of Reports the head of Prague hygiene Zdeňka Jágrová.