Survey: Amount of coronavirus in wastewater moderate almost all over Estonia

TALLINN – The findings of this week's survey in a series of surveys of wastewater samples from all over Estonia for coronavirus, led by the University of Tartu, show that coronavirus has spread more evenly across Estonia compared to last week and there are no settlements with a very large amount of the virus on the map this time, while there are fewer places with a small amount of the virus.

Tanel Tenson, lead researcher of the study and professor of technology of antimicrobial compounds of the University of Tartu, said that compared to the index characterizing the average situation in Estonia, the amount of coronavirus is somewhat higher in Harju County and South Estonia. This week, in addition to larger settlements, wastewater samples were also taken from smaller places, a total of 60 sites. "The results show that the virus is spreading more rapidly rather in larger settlements. In smaller places, the situation is still quite calm," Tenson said.

Wastewater samples are collected at the beginning of every week in all Estonian county centers 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. This week, samples were taken only in the major cities, as samples from major cities reflect the situation of wastewater 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 Center and water companies operating the waste water treatment plants of Estonian cities. The samples are analyzed at the laboratories of the University of Tartu's Institute of Technology.