Last week we presented the results of our reader survey, which indicated that many of you thought COVID-19 was circulating in your communities more in recent weeks than it had been at any other point in the past year.

This week, we have the latest results of a more scientific poll — the Household Pulse Survey conducted by the U.S. Census Bureau. Since 2020, this poll has been consistently asking Americans a range of questions every few weeks, including about whether they’ve had COVID.

In June 2022 they started asking if people had had COVID within the past four weeks. So we took a look at how Minnesotans have responded to that question since last summer. (They also switched at that time from asking if the person surveyed had been diagnosed with COVID to asking if they had been diagnosed OR tested positive with a rapid test, so it’s hard to compare data from before and after June 2022.)

The results from the first two weeks of February — which match up pretty well with the timing of our reader survey — show it was actually one of the calmer periods of COVID circulation. Last summer had the most respondents saying they had recently had COVID, with the number steadily declining to a low in mid-November. It picked back up again over the winter holidays, before falling again in early February.

What can we make of the discrepancy? The most obvious explanation is that people were more likely to answer our reader poll if they knew someone who had recently had COVID.

Another explanation is due to the networked nature of disease spread. People who belong to networks where COVID is circulating experience COVID as being more prevalent. Our reader poll could have tapped into those networks where COVID was circulating at higher rates.

This logic could apply to the Household Pulse Survey. It’s possible that the sample of respondents in early February just so happened to be less connected to networks in which COVID was circulating. But, given the survey’s design to capture a random sample of Americans, it’s less likely that this was the case for the household survey compared to our reader survey.

Also, as testing has moved away from official venues to at-home tests, it’s possible that people have been less inclined to test themselves or immediate family members, especially if symptoms are mild. The Census Bureau may have reached a sample of Minnesotans who have recently been less vigilant about testing compared to the sample of our readers.  

It’s more likely that the on-the-ground situation for Minnesota is better represented by the Household Pulse results than our reader poll. This doesn’t detract, however, from the fact that for many of you, COVID was circulating much more prevalently in recent weeks than at other times over the last year.

But one big takeaway is that no single data set has all the answers, especially when it comes to COVID. It’s better to look at multiple data sets and always think about what blind spots a given data set has, and how they can be balanced by other data sources out there. That’s why we bring you a variety of metrics every week, along with their sometimes-lengthy caveats and qualifiers. Read on for the latest metrics.  

Most statewide data shows declines in COVID, but ICU admissions have ticked up

Officially reported cases, which come primarily from positive tests at healthcare facilities, are down this week across the state. While this data does not include people who take a rapid test at home, it does provide an indication of the number of people seeking health care who test positive.

After falling or staying steady the past few weeks, intensive care unit admissions for COVID are back up again in the most recent week of data. Non-ICU admissions, on the other hand, have fallen to a new low not seen since last spring.

The number of COVID-related deaths has continued to decline over the past few weeks. In the past couple of years, there was also a steep decline around this time each year, following much larger waves of COVID mortality than we have seen this winter.

COVID wastewater data shows increased levels in Twin Cities metro

Twin Cities metro update

The total level of virus increased by 29 percent for the week ending Feb. 20 compared to the previous week, according to the latest data from the Metropolitan Council and the University of Minnesota’s Genomic Center. The XBB subvariant now comprises 82 percent of the viral RNA load entering the Metro wastewater plant. According to Bonnie Kollodge at the Metropolitan Council, “The total RNA viral load is the highest it has been since Dec. 20-26, but the variant mix has changed completely.”

COVID levels in wastewater now are overall much steadier compared to the large swings in the past, especially last winter’s massive omicron spike. While there are still some relative ups and downs, we continue to see this “plateau-like” phase of the pandemic persist.

Also notable is that in early 2021, there was less COVID in wastewater than there is now and it was on the decline, but there were many more deaths than we’ve seen in early 2023(see previous graph). The impacts of COVID-19 are not over, but it’s not causing the acute waves of severe disease that it once was.

Statewide update

COVID levels in wastewater increased throughout the state over the prior month but appear to have leveled off more recently in many regions, according to the latest data out of the University of Minnesota’s Wastewater SARS-CoV2 Surveillance Study. For the period ending on Feb. 8, the study’s Central and South West regions saw a substantial four-week increase in COVID-19 load of over 100 percent each. The one-week change in those regions, however, shows COVID loads that are levelling off.

The North West and South Central regions also saw relatively large four-week increases, and those two regions had the highest one-week increases, at 39 percent and 42 percent, respectively.

The Twin Cities Metro (the study’s largest region) experienced an increase of 25 percent over the prior four weeks, while the North East and South East regions experienced more modest increases over the prior month.

In terms of variant prevalence among samples from COVID cases, Veronica Marshall from the Minnesota Department of Health shared with the APM Research Lab that “XBB increased to 62 percent of sequenced samples in the current period, compared to 43 percent in the last period.” She also noted that “This is the fifth consecutive two-week period of growth for XBB lineages.”

High-and medium-risk counties in western and southern Minnesota; much of state at low risk according to latest from CDC

 Western and southern portions of the state are at heightened risk, but much of Minnesota remains at low risk, according to the latest Centers for Disease Control and Prevention “Community Level” COVID-19 assessments. Only Big Stone and Traverse counties are rated high risk for the week ending Feb. 22, down from six high-risk counties last week. Both counties have COVID-19 hospitalization rates of 22 per 100,000, which places them over the high-risk threshold.

Although fewer counties are rated high risk this week compared to last week, there are more than twice the number of medium-risk counties. The 29 counties the CDC rated medium risk this week are largely concentrated in western and southern Minnesota. Clay County, which contains the city of Moorhead, and Olmstead County, which contains the city of Rochester, are both rated medium risk this week due to COVID-19 hospital admission rates of 10 or more per 100,000.

This week 14 counties have case rates that meet the CDC’s definition of high transmission (weekly case rates of 100 or more cases per 100,000), a significant decrease from the 35 counties that met this threshold last week. Unlike last week, no counties have a case rate that exceeds 200 cases per 100,000, although Nobles and Pipestone counties come close with case rates of 199 and 197 per 100,000, respectively.