COVID-19 levels are down 16% in Twin Cities wastewater

Sewage sampling this week at the Metropolitan Wastewater Treatment Plant in St. Paul found a 16% decline in levels of the coronavirus that causes COVID-19.

The decline in viral load coincides with reductions in coronavirus infections in Minnesota and counties designated at high COVID-19 risk levels by the Centers for Disease Control and Prevention (CDC) . Five counties are now listed at high risk, down from 10 last week.

Mask-wearing in indoor public places is recommended in Nicollet, Kanabec, Olmsted, Winona and Houston counties because of these risk designations, which are based on local COVID-19 case and hospitalization numbers. The seven-county Twin Cities metro area is listed at moderate risk.

Gov. Tim Walz still urged people to seek testing if they experience any COVID-like symptoms and to limit the spread of the virus, which remains threatening to the elderly and others with elevated risks.

Minnesota on Friday reported another 12 COVID-19 deaths — 11 involved seniors who have made up 80% of the state's total of 12,713 deaths in the pandemic.

"We are still in a moderate to high risk even this far into summer. So, if you're feeling those symptoms, test as you can," Walz said Thursday while visiting the state's Brooklyn Park testing site that provides rapid access to antiviral pills for vulnerable people who test positive.

Concerning BA.4 and BA.5 coronavirus subvariants made up 32% of the viral material found in Twin Cities' wastewater samples from May 31 through Monday — an increase from 23% a week earlier. However, the fast-spreading variants are making up more of a shrinking pie. The amount of viral material reported by the Metropolitan Council is at its lowest since late April.

The Twin Cities results match with broader sewage sampling at 40 plants across Minnesota that cover 67% of the state's population. Viral levels through Sunday had leveled off or declined in all seven wastewater monitoring regions of the state.

Wastewater sampling is considered a stable indicator of COVID-19 activity because it isn't affected by changes in the number of tests performed — or whether people only use at-home tests that aren't reported to the state.

Minnesota on Friday reported 409 COVID-19 hospitalizations, including 34 requiring intensive care. Health officials say short-term immunity as a result of vaccinations and recent infections has reduced the toll of the latest wave and the number of severe COVID-19 cases requiring intensive care.

While Minnesota has identified infections among 1.5 million residents, the CDC estimated through mid-February that the actual count in the state was nearly 3.4 million. The estimate is based on checks for COVID-19 antibodies in blood specimens submitted for various medical tests. If correct, the estimate means that more than 60% of Minnesotans have been infected at least once.