Wastewater study map shows few places with high virus readings

The map of the results of this week’s wastewater monitoring study shows few settlements with high and very high coronavirus readings to a predominantly green background. Compared to the index representing the average situation in Estonia, virus readings are slightly higher in Harju County, Ida-Viru County and in central Estonia.

Over the week, the overall picture has become greener, i.e. the concentrations are low. However, also places with high and very high virus concentration have reappeared on the map. “Coronavirus concentration has become very high in the area of the Viimsi-Muuga wastewater treatment plant, as well as in Ahtme. The virus amounts in samples from Jõhvi and Rapla treatment plants are slightly smaller, but still considerable. Even so, the index representing the average situation in Estonia has still remained stable at quite a low level for the last four weeks,” said lead researcher of the study Tanel Tenson, Professor of Technology of Antimicrobial Compounds at the University of Tartu.

How and where are tests gathered?

Waste water samples are collected at the beginning of every week in all Estonian county centres and cities with more than 10,000 inhabitants. In the period of more extensive spread of the virus, samples were also collected from smaller settlements, as needed. As the spread of the virus has been moderate in Estonia in the last weeks, this time no samples were taken from smaller places.

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.

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

In collecting the samples, the University of Tartu cooperates with the Estonian Environmental Research Centre and water companies operating the waste 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, University of Tartu, 5344 5202, tanel.tenson@ut.ee