Health

Respiratory illnesses low, TB bouncing back to pre-COVID levels

Plus, new study on long COVID and brain fog

two person walks on the corridor
After slowly rising for a couple of months, COVID hospitalizations have plateaued in recent weeks.
Erica Dischino for MPR News

Influenza concerns remain low in Minnesota, RSV (respiratory syncytial virus) hospital rates are up slightly and COVID hospitalizations have plateaued in recent weeks after slowly rising for a couple of months.

Meanwhile, researchers continue to uncover more about long COVID. One study of note this week found that lingering symptoms of brain fog could stem from lingering viral presence disrupting the production of serotonin. Much more on that from NPR here.  

Researchers have also identified lingering viral presence in the body as a likely cause of the heart-related aftereffects of COVID, which we wrote about in our last update.

More broadly, scientists have established evidence that viral material can remain in “viral reservoirs” even after active, systemic infection has passed. But exactly how the viral material may be contributing to long COVID is the major question researchers are starting to be able to answer in some of these recent studies. 

If you’ve managed to avoid any long COVID effects so far, you may not be out of the woods yet. According to the health news site STAT, you can get long COVID from a reinfection even if you didn’t get it after your first infection.

The report also says that vaccination reduces your chances of getting long COVID. Our update last month details the latest on preventing COVID, RSV and flu.  

If you or someone you know gets COVID here’s the latest advice from the CDC

More on the latest COVID data in Minnesota below, but first we spotlight an illness that is much rarer, but on the rise, in the state — tuberculosis.  

Tuberculosis returning to pre-pandemic levels 

After a drop off in the number of reported tuberculosis cases in the U.S. in 2020—down 20 percent from 2019 — those numbers have steadily risen. In 2022 there were 8,300 reported TB cases across the country, up from 7,874 in 2021.     

Recent preliminary data from the Centers for Disease Control and Prevention for 2023 indicates that the number of TB cases in the U.S. is continuing to climb. In 2023, year to date, 20 states and the District of Columbia have reported higher case counts than they did at this time last year, including Minnesota.    

Considering the percent change in reported cases from 2022 year-to-date to 2023 year-to-date, however, Minnesota has only seen a six percent increase in reported cases, from 80 to 85. That makes it the state with the third-lowest increase among those that have seen an increase in 2023.  

In an email response to the Research Lab, Sarah Gordon, Manager of the TB Prevention and Control Program at the Minnesota Department of health noted, “In 2020, the reported 117 TB cases reflected a three-decade low in TB case reports. The increase in cases from 2020 to 2021 reflects a return to expected TB incidence, and Minnesota is expected to see higher numbers in 2023, which is still an expected return to pre-pandemic norms.”  

Gordon also stressed that TB is rare in Minnesota and the United States overall, especially “as compared to globally, where TB remains the leading infectious disease killer, surpassing HIV in 2014.”  

“Due to public health efforts,” Gordon assured, “TB is not a risk to the general public in Minnesota.”  

See the Minnesota Department of Health’s website for more information about TB in Minnesota. 

COVID hospitalizations plateau, remain relatively low 

Due to changes in how COVID cases are reported, we no longer include case-related data in our updates. Trends in hospitalizations can, however, give some indication of whether COVID is generally on the rise or declining in the state.   

The increase in COVID hospitalizations has slowed the last few weeks compared to the faster rise seen over the previous couple of months, but we can’t say we have reached the peak of this ongoing wave yet. In the week ending Oct. 17, 241 people were admitted to the hospital with COVID illness in Minnesota.  

Nonetheless, the recent “wave” is more like a ripple compared to years past. In 2020 and 2021, hospitalizations skyrocketed starting in the August - October time period, and we haven’t seen anything like that yet. In 2022, there was a more stable level of COVID hospitalizations, but they were approximately twice what they are this year.

Comparison of ICU and non-ICU COVID hospitalizations throughout pandemic
Hospitalizations from COVID remain low compared to mid-October in the past three years.
David Montgomery

Modest decreases in recent wastewater levels

While hospitalizations can signal if COVID is on the rise, there is some delay to that signal, since an increase in hospitalizations will lag an increase in cases. COVID levels detected in wastewater, on the other hand, are considered to be more of ‘an early warning’ for shifts in COVID trends. 

The latest statewide wastewater data shows a modest decline in COVID-19 levels in Minnesota. COVID-19 levels decreased by roughly five percent when comparing the most recent reading, Oct. 15, to one week earlier.

This statewide decrease reflects declines in four of the seven regions in the University of Minnesota’s Wastewater Surveillance Study. Two of the remaining regions were relatively stagnant, with increases under one percent; the South West region was the only one to see a moderate weekly increase of around 16 percent.  

This data point isn’t necessarily cause for alarm since the South West region’s weekly increase should be read against a monthly decline of 42 percent as of Oct. 15.