The figure shows the relative amount of SARS-COV-2 in Gothenburg wastewater week by week, starting mid-February 2020 (week 7). Week numbers on the X-axis.
Photo: Göteborgs universitet

Coronavirus levels in Gothenburg wastewater


Changes in corona virus levels in wastewater are directly relatable to the number of people infected. Follow the measurements from the University of Gothenburg and see how the pandemic develops in the area – week by week.

Heléne Norder, Institute of Biomedicine, Sahlgrenska Academy at the University of Gothenburg.
Photo: Elin Lindström

Since February 2020 a research group led by Heléne Norder at Sahlgrenska Academy, University of Gothenburg, has been investigating the presence of SARS-CoV-2 in Gothenburg wastewater. The latest result shown in the figure above is from last week, September 5-11, 2022.

The surveys are carried out in collaboration with the municipally owned company Gryaab, which treats wastewater in Gothenburg and the surrounding municipalities, and sends the scientists one sample a week, composed of samples collected daily.

The measurements and analyses have attracted a great deal of attention during the pandemic. The weekly reports have shown both how widespread SARS-CoV-2 infection is in the community and its distribution among variants of the virus.

In a scientific study, publishes in iScience, the research group established the fact that monitoring of viruses in wastewater enables the course of a pandemic and its burdens on various parts of the health-care sector to be predicted. This is independently from official public testing capacity and scope for infection tracking.

According to the study each of the four pandemic waves in Sweden 2020–2022 exhibits a pattern in which, within a couple of weeks after SARS-CoV-2 peaked in the wastewater, a rise in the number of newly admitted hospital patients with COVID-19 ensued.

The virus peaks in the wastewater were followed not only by heavier burdens on inpatient care, but also by predictable increases in pressure on the 1177 Vårdguiden e-service. One to two weeks after a wastewater virus peak, more calls were coming in about acute breathlessness in adults.

The method used in Gothenburg also enables monitoring of other viruses, which gives unique scope for quickly spotting ongoing outbreaks, besides SARS-CoV-2, for example the norovirus, the ‘winter vomiting bug’, and astrovirus among children.