RSV rising rapidly; COVID-19 continues its climb and flu season is underway

Published 6:25 pm Friday, December 1, 2023

Getting your Trinity Audio player ready...

By Benjamin Clary and Craig Helmstetter

Respiratory illnesses are on the rise. COVID-19 and more recently influenza have been leading to more hospitalizations, but respiratory syncytial virus (RSV) is currently increasing fastest among the three in the Twin Cities seven-county region.

Over the most recent two weeks, the number of RSV-related hospital admissions in the Twin Cities more than doubled, compared with increases of about one-quarter for both COVID-19 and the flu. For the time being, however, COVID-19 hospitalization rates in the region, at 5.6 per 100,000, remain much higher than either RSV (1.9 per 100,000) or influenza (0.5 per 100,000).

Email newsletter signup

The rates of all three — COVID-19, influenza and RSV — remain much lower than this time last year when both the RSV and flu seasons peaked early, before Thanksgiving. It is unlikely that we’ve reached the peak for this season given the relatively low levels of activity so far.

RSV: On the rise, especially among the youngest

While RSV-related hospitalizations are growing overall, the increases are most dramatic among those most susceptible to the virus: young children. In the Twin Cities, 47 of the 58 RSV hospitalizations during the week starting Nov. 12 were among those age 0 to 4.

The hospitalization rate among those youngest Twin Citians was 11.7 per 100,000. That is notably higher than the overall rate of 1.9, not to mention the rate of 0.7 among the other group most vulnerable to RSV, those 65 years of age or older.

Among the concerns with the current increase in RSV: The data suggest the state may soon run out of pediatric hospital bed capacity. Department of health data show there are currently only 36 unoccupied pediatric beds in the state, and only 14 in pediatric intensive care units. Those beds will quickly fill if new RSV admissions for children, currently around 60 per week, get anywhere near last year’s peak of 155 per week.

The CDC recommends RSV immunization for those who are 32-36 weeks pregnant, babies up to 8 months old whose mother did not receive the vaccine and those age 60 and older. RSV vaccination rate data are not readily available, but as of Nov. 25, 14.8 percent of those 60 years of age or older had received an RSV vaccine. This is notably lower than the 60 percent of those in that age group who said they would get vaccinated according to a survey conducted by KFF in early September.

Influenza: Picking up, but rates are still low in Minnesota

This year’s influenza season is under way. According to the CDC’s latest “FluView” update, nationwide flu-related hospitalizations doubled over the past three weeks. The same report indicates that flu activity remains relatively minor in Minnesota. In fact, the state is one of only five in the brightest green “minimal” category, down from 12 states two weeks earlier.

Minnesota Department of Health data show that the flu is among many racial and ethnic health disparities in the state. In the height of last year’s flu season, flu-related hospitalization rates reached over 20 per 100,000 among both Black and Indigenous Minnesotans, compared to nine per 100,000 among Asian Minnesotans, eight per 100,000 among white Minnesotans and less than three per 100,000 among Hispanic Minnesotans. That same pattern is already beginning to emerge this year.

Although the CDC’s state-level data on flu vaccination currently lags back to mid November, at that time Minnesota’s adult vaccination rate, 43 percent, was somewhat higher than the national rate of 37.5 percent.

COVID-19 continues its upward creep, especially among older Minnesotans

After a downward blip during Halloween week, the number of COVID-19-related hospital admissions has climbed back up. The preliminary count for the week ending Nov. 21 is 337. This is likely to be revised upward as data are firmed up, but that number is the highest level of weekly COVID hospital admissions since February.

Importantly, the climbing number of hospital admissions in Minnesota is hitting older adults particularly hard. While a disproportionately high number of older adults have ended up in the hospital due, at least in part, to COVID-19 throughout the pandemic, that is particularly the case now.

For example, while only seven percent of Minnesota’s population is age 75 or older, that age group made up 36 percent of those hospitalized at the pandemic’s first peak in late Nov. 2020. Then, in the Jan. 2022 peak about 20 percent of those hospitalized with COVID-19 were 75 or older. For the past several months about half of the state’s COVID-19 hospitalizations have been among those age 75 or older.

As a result, the weekly COVID-19 hospitalization rate for Minnesotans age 75 or older is now more than 40 per 100,000; this is at least six times the rate of the general population in Minnesota and similar to the rates for that age group throughout much of 2022. It is also higher than the 30 per 100,000 weekly COVID-19 hospitalization rate for Minnesotans at the very peak of the pandemic.

Perhaps in response to those impacts, uptake of the new COVID-19 vaccine is highest among older Minnesotans: 44 percent of those age 65 or older, compared to 14 percent for Minnesotans of all ages. As reported by Axios Twin Cities, the latest CDC data show that uptake of the new COVID vaccine, 27 percent of adult Minnesotans, is among the nation’s highest (the national rate is 16 percent).

COVID-19 levels in wastewater continue to rise

The latest data from the University of Minnesota’s Wastewater Surveillance Study shows continuing increases in COVID-19 levels, which increased roughly 21 percent statewide when comparing the most recent week, Nov. 22, to one week earlier.

The wastewater levels in all seven of the study’s regions increased or remained relatively flat over the prior week. And the North West, South West and Twin Cities regions each saw increases in their COVID-19 levels above the statewide average.

Over the prior month, the study’s seven regions experienced solid increases in COVID-19 levels. The statewide average increased by 70 percent. COVID-19 levels in the North West region increased by over 100 percent, the only region to more than double their COVID-19 levels.

Statewide COVID-19 levels in wastewater are at their highest point in six months, but they remain below where they were in the first three months of the year.

Recently the Centers for Disease Control and Prevention updated their reporting on COVID-19 wastewater viral activity. As of Nov. 25, Minnesota is one of 10 states in which the viral activity is deemed “very high” by CDC. However, this designation is based on preliminary data, so they should be seen as an indication of trends but not the final word..

With the continuing increases in wastewater levels seen in the University of Minnesota’s study, as well as increasing hospitalizations due to COVID, RSV and influenza, Minnesotans may want to take precautions during the upcoming holidays, including testing for COVID-19 before gathering, getting up to date on vaccinations, and even consider masking especially in large, indoor gatherings or when around people with higher risks.