This week’s results of the waste water analysis led by the University of Tartu show that the amount of coronavirus in waste water in Estonia remains quite stable. Domestic spread of the Omicron variant has not yet led to an explosive increase in infection.
Lead researcher of the study, the University of Tartu Professor of Technology of Antimicrobial Compounds Tanel Tenson admitted that while other countries in the world have reported record infection numbers in the last few days, the situation in Estonia still remains calm. “We have noted a slight increase in the virus amount. The last few weeks have also seen a steady increase in the number of cities where the Omicron strain is present. So far, this strain has not become widespread yet. However, it is probably only a matter of time, so it would be a good idea to take precautions during New Year celebrations, and prefer outdoor and smaller gatherings to crowded indoor events," said Tenson.
How and where are the samples collected?
Waste water samples are collected at the beginning of every week in all Estonian 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. The 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 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 to estimate the spread of the virus before clinical cases are detected.
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 research methodology has been developed by University of Tartu scientists. Next year, the Health Board will conduct the regular waste water study, but cooperation with our researchers continues. Tenson said that the researchers will participate in the waste water monitoring study as advisers, because new information is constantly emerging about the coronavirus and the research methodology may have to be adapted from time to time.
For more information about the previous results of the study, see the home page of the study “Detecting coronavirus in waste water”. In future, the waste water study results can be found on the website of the Health Board.
The waste water study is funded by the European Regional Development Fund from the EU measure to respond to the Covid-19 pandemic.
Map: Results of the waste water survey 27–31 December. University of Tartu