As COVID-19 cases in Minnesota rise, hospitals fill

New coronavirus cases in Minnesota surpassed 4,000 for the third straight day on Tuesday, following a record-breaking surge on Sunday with more than 5,900 new daily infections, according to state health department data.

The seven-day average for hospitalizations has risen nearly 142% over the past month. With 1,000 patients hospitalized Monday and 92% of ICU beds full, Gov. Tim Walz requested federal aid to support hospitals and long-term health facilities experiencing shortages, according to an internal Health and Human Services memo obtained by ABC News.

Hospitals in the Twin Cities are now declining patient transfers from neighboring states like North Dakota and Iowa, according to the HHS memo.

The Minnesota Department of Health confirmed to ABC News last month that at least 23 coronavirus cases had been linked to three in-state Trump campaign events in September.

Minnesota's rising infections are part of a COVID-19 wave that's swept the Midwest this fall, according to Dr. Amy Williams, a dean for practice at the Mayo Clinic in Minnesota. In addition to new cases, the Midwest's positive testing rate has increased "exponentially over the last four weeks," she said.

In Minnesota, as of Monday, an average of 13.5% of tests returned positive every day in the past week, according to an ABC News analysis of data from The COVID Tracking Project, a rate nearly three times higher than health experts recommend. A high positivity rate can be a sign that a state is only testing its sickest patients and failing to cast a net wide enough to accurately capture community transmission, according to Johns Hopkins University.

Williams called a positivity rate higher than 10% "very, very serious," noting that it's a threshold at which experts start to worry about having the capacity to care for COVID-19 patients.

Although new cases grew among all age groups, people in their 20s made up the bulk of new confirmed cases, according to the HHS memo. Although older patients, who are at higher risk for COVID-19 complications and death, were hospitalized more often at the beginning of the pandemic, Williams said younger and younger patients are now being being hospitalized.

In response to the widespread surge of COVID-19 cases across the state, Walz announced on Tuesday that the state would implement new restrictions, including mandating that bars and restaurants close at 10 p.m, and limiting indoor and outdoor private social gatherings to 10 people. Additional restrictions, like limited funerals and weddings to 50 people, will be phased in in the coming weeks.

ABC News' Josh Margolin contributed to this report.

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