A recent waste water survey conducted by the University of Tartu found significantly raised concentrations of coronavirus.
Lead researcher in the TÜ study, Professor Tanel Tenson, noted the figures were the highest since the regular surveys began, with 14 out of 20 wastewater samples showing very high concentration, compared with about a half of samples last week (see map below).
Tenson said: "I can say that our samples have never before shown such a high viral level. The results allow us to deduce that the number of infections has increased a lot almost everywhere in Estonia."
This rise is somewhat borne out by recent case rates in Estonia, which have been high, though stable, Hanna Sepp, Head of the Health Board's Department of Infectious Diseases Surveillance and Epidemic Control.
"The number of new COVID-19 cases has been very high in the recent weeks, though rather stable. There is also a persistently high level of positive tests indicating latent spread. Also the number of people in hospital care has remained on a stable level." Sepp said, via a press release, adding that a rise in infections was expected after last week's easing of restrictions and standardization of them nationwide (Harju and Ida-Viru counties had for several weeks been subject to stricter measures than the rest of the country – ed.).
One of several means of obtaining overall COVID-19 picture
"While the results of this study are not always consistent with the number of COVID-19 cases identified, the study proactively helps us focus our attention and actions, and build preparedness," she added.
Sepp says the ongoing wastewater monitoring is a useful means getting a picture of the overall viral situation in Estonia, in addition to the other yardsticks, including daily infection rates.
While recent high virus readings in waste water samples, which were found nationwide, are definitely alarming and call for vigilance, though these other measurements do not indicate a surge in infections, Sepp said.
Wastewater samples are collected on a weekly basis in towns with a population over 10,000 (13 population centers – ed.) in conjunction with the water companies serving those areas, and the Estonian Environmental Research Centre (EKUK)
The wastewater samples themselves are analysed at TÜ's Institute of Technology labs.
Editor: Andrew Whyte