Minnesota hospitals admitted 117 influenza patients last week, the highest weekly total for the season, according to a Minnesota Health Department flu update on Thursday.
The department also revised the prior week's tally upward, to 114, an adjustment that reflected reporting delays. So far, 505 people have been hospitalized for the flu, which is about the midrange for recent influenza seasons.
Schools had become ground zero for many infections over the past few weeks, but as expected, there were no school outbreaks in the last full week of 2019 because of the holiday break.
Clinics are also seeing a surge of patients with flu-like symptoms, who represented 5.8% of all clinic visits last week — a level of activity often seen as the season approaches its peak.
Typical flu-like symptoms include fever, body aches, chills and coughing, as well as general upper respiratory unpleasantness.
Most of the patients tested were infected with the B strain of the virus, which, unlike previous years, emerged early in the current season.
The B strain is more likely to affect children — reflected in the surge of school outbreaks earlier this year — because fewer of them have been exposed to it in the past and had the chance to develop immunity.
"A higher fraction of adults have seen [the B strain]," said Dr. Frank Rhame, an infectious disease specialist at Allina Health.