Coronavirus found in wastewater in Helsinki, Turku

Coronavirus has been detected in the waste water in Helsinki and Turku, according to the National Institute for Health and Welfare (THL).

THL’s waste water study, however, did not find the virus in samples collected in Tampere, Kuopio and Oulu, said a THL press release on Tuesday.

In April and May, THL’s water microbiology laboratory in Kuopio introduced a testing method which can be used to detect the quantity of coronavirus RNA, or its genetic material, in samples collected from sewage treatment plants.

The waste water study is expected to generate more information about the scope and spread of the coronavirus outbreak.

“Confirmed infections indicate an abating epidemic situation, and waste water studies support the observations based on testing individuals. Waste-water-testing can give us an advance warning if increasing quantities of the virus start circulating in the population again,” said THL Senior Researcher Tarja Pitkänen.

The collection of samples began in April at a total of 28 sewage treatment plants. For the time being, samples are collected weekly from water treatment plants in Helsinki, Turku, Tampere, Kuopio, and Oulu. In addition, samples will be collected on a monthly basis from the following localities: Espoo, Maarianhamina, Kotka, Kouvola, Lahti, Hämeenlinna, Lappeenranta, Pori, Mikkeli, Savonlinna, Jyväskylä, Joensuu, Seinäjoki, Vaasa, Kokkola, Kajaani, Kemi, Rovaniemi, Salo, Rauma, Pietarsaari, and Vihti.

The next step will be investigating the possibilities of reliably determining the quantity of coronavirus. The results of these tests are likely to be ready in August.

“We also need to know if the coronavirus can remain viable in the water coming to sewage treatment plants,” said Pitkänen.