No changes in the amount of coronavirus in waste water

This week’s results of the waste water analysis led by the University of Tartu show that the amount of coronavirus remains stable at a high level. For several weeks already, southern Estonia stands out with the highest virus levels. Coronavirus was not found in the samples collected from Pärnu County and Hiiumaa. 

According to the lead researcher of the study, Professor of Technology of Antimicrobial Compounds of the University of Tartu Tanel Tenson, the amount of coronavirus detected in the samples taken from southern Estonia is double the index describing the average situation in Estonia. The virus has been slightly spreading also in Harju County, where, compared to previous weeks, the virus amount has increased in smaller places. “At the same time, the general level of virus is stable in Estonia, without remarkable increase or decrease. So we can expect the infection level to remain stable in the coming weeks,” said Tenson.

How are the samples collected?

Waste water samples are collected at the beginning of every week in all county centres, cities with more than 10,000 inhabitants and, if necessary, in smaller settlements. Samples taken from larger cities reflect the situation of waste water passing through the treatment plant over 24 hours, giving a reliable overview of the infection level in the city.  Spot samples taken in smaller places show the situation at the moment of sampling. Spot samples are more easily affected by various factors and should therefore be used in comparison over several weeks to estimate the trend, rather than get a definitive picture of the current situation.

The study is a tool helping the Health Board monitor changes in the outbreak dynamics and discover hidden outbreaks. It gives early information for estimating the spread of the virus before clinical cases are detected. The Health Board is regularly informed of the results.

In the collection of samples, the University of Tartu cooperates with the Estonian Environmental Research Centre and water companies operating the water treatment plants of Estonian cities. The samples are analysed at the laboratories of the University of Tartu Institute of Technology.

For more information about the previous results of the study, see the home page of the study “Detecting coronavirus in waste water”.

Further information: Tanel Tenson, Professor of Technology of Antimicrobial Compounds of the University of Tartu, +372 5344 5202,