Southeast Minnesota counties will see COVID peaks at different times
Mayo Clinic modeling forecasts Olmsted County to see early peak with highest rate in the region.
ROCHESTER — The COVID-19 surge connected to the omicron variant is expected to peak in Olmsted County as early as next week, but some of the surrounding counties rates may continue to increase into February.
Mayo Clinic’s latest forecast through predictive modeling estimates Olmsted County’s average daily cases could peak Jan. 27, a day after a projected statewide peak.
While most surrounding counties are expected to peak later, Olmsted County has the distinction of having the highest COVID-19 incidence rate in the state, according to Meaghan Sherden, Olmsted County’s lead epidemiologist.
The higher rate is being occurring despite the county having the state’s second-highest vaccination rate.
“I think that comes with a couple caveats, but don’t get me wrong, we have a ton of COVID in the county,” Sherden said.
She cited the area’s increased testing capacity, along with a medical community that is actively driving efforts. The combination has likely helped identify cases that could have been overlooked elsewhere.
Olmsted County saw testing nearly double week-over-week earlier this month, with a positivity rate just below 30%.
Mayo Clinic data scientist Curtis Storlie, who has been working with predictive modeling to forecast COVID surges, said Olmsted County has reported lower rates of infection by the delta variant, leaving more people susceptible to omicron.
“A combination of previous infection and vaccination has been more protective against omicron infection than vaccination alone,” he said. “Vaccinations more than five months ago have not been particularly effective at preventing omicron infection. A recent booster has shown much better efficacy at reducing infection risk.”
While Olmsted County’s peak is projected to be earlier and higher than what is expected surrounding counties, Storlie said it’s not necessarily a lot higher.
“Goodhue, Dodge, Fillmore, Winona, etc., all look like they are projected to peak at similar, high levels of cases, but a bit later than Olmsted,” he said.
The forecasts continue to shift slightly based on new information, since the past and current average daily case rates are determined through the seven-day rolling averages collected by county at the state level.
While the statewide peak is expected to happen shortly before Olmsted County’s cases start to decline, Storlie warned against comparing state changes to individual counties, since the statewide trend is weighted by the averages from all 87 counties.
Once their peaks arrive, he said counties can expect abrupt declines in cases for several weeks.
“We are starting to see that around the country,” he said.
Sherden pointed out it will take time for the region to emerge from what the Centers for Disease Control and Prevention has defined as a high rate of community transmission, which is any county with a rate of more than 100 new cases in a seven-day period per 100,000 residents.
Olmsted County’s latest reported rate was 1,229.
Storlie said the anticipated rapid decline after the peak doesn’t mean people will be able to let their guards down.
“Hitting the peak doesn’t mean it’s behind us,” he said. “People are going to continue to get infected on the way down, just as many on the way down as on the way up.”
At the same time, he said it’s unlikely that additional peaks will follow in the near term.
“We will have a pretty robust immunity here for awhile for a honeymoon period, and cases will be low for several months, in all likelihood,” he said. “Then it’s up to us. How willing are we to take this seriously and prevent another surge from another variant in the future.”