SLU believes more of the pandemic is in wastewater — but the peak has been passed

Local COVID-19 outbreak alerts have been raised in various locations in Sweden and abroad in recent weeks. The infection is also showing up in Swedish wastewater.

– Don't expect it to rise during the summer, but it has been that way since 2022, when the first Omicron wave appeared, says Anna J. Szekely.

There are more SARS-CoV-2 viruses circulating than last year:

– Virus levels in sewage are higher than last summer.

Since the start of the pandemic, Anna J. Szekely has been tracking virus levels at treatment plants across the country where wastewater is sampled. SLU coordinates the sampling and analysis on behalf of the Public Health Agency, which in turn conducts further analysis.

– Today we have 19 measuring stations covering about 43 percent of the population. In cooperation with the Public Health Agency, we have selected relevant places where many people live, but we still have a geographical spread from Luleå in the north to Malmö in the south, says Anna J. Székely.

In recent weeks, some places have stood out in terms of Covid.

– The latest data we were able to analyse dates back to July 15 – when virus levels started to decline in all places except Örebro.

However, the highest levels of the virus were not in Örebro.

– That was in Östersund, during week 28. And in week 28, we reached the peak throughout the country. There were also high levels in Västerås that week.

Aside from the fact that virus levels were higher this summer than during the same period last year, the trend appears to be quite similar, says Anna J. Székely.

– It started as a slow rise in June and peaked in the second week of April.

Anna Székely and her colleagues at SLU don't expect any more peaks this summer — quite the opposite.

– July is a big holiday month, and as we've seen in previous summers, it usually suppresses infections.

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Lakartidningen.se 2024-07-23