In what is likely to be a record year for influenza cases and hospitalizations in South Dakota, schools have been hit particularly hard by illnesses this winter.
When several students fell ill and then a few teachers also became sick in late January, Menno schools superintendent Kory Foss made the decision to shut down the district for a day.
During one peak period for flu cases statewide, Foss thought closing schools on a Friday would give the sick students and staff a long weekend to recover.
“We cleared out the buildings to give everybody a chance to go home and get healthy,” said Foss, whose district of 45 employees and about 260 students is located in Hutchinson County, about 30 miles north of Yankton. “Our whole area around that time, there were a number of schools that were hit hard.”
Tough year for respiratory illnesses
Data from the state Department of Health confirm that the winter of 2024-25 has seen a higher-than-usual number of infectious diseases cases around the state.
At the two-third mark of the annual nine-month flu season, South Dakota in 2024-25 has seen 19,600 cases, 1,079 hospitalizations and 28 deaths from influenza. The state is on pace to set a record for cases and is already at a historic high in hospitalizations from influenza.
South Dakota state epidemiologist Joshua Clayton told News Watch that the state has seen a somewhat unusual mix of illnesses this year, including COVID-19, influenza, norovirus, respiratory syncytial virus (RSV) and pertussis, or whooping cough.
"I won't say that it's kind of a perfect storm, but I just know there is a lot of respiratory disease happening in South Dakota right now," he said.
Schools are often an ideal breeding ground for contagious diseases because hundreds of adults and children congregate together for long periods of time, especially when cold weather prevents them from going outside. The cold snaps in January and February were also marked by extremely dry air, which allows viruses to remain in the air longer and possibly spread more easily, Clayton said.
As of Feb. 11, the state had tallied 2,450 cases of COVID and 56 cases of pertussis, which is more dangerous in children. The state does not report numbers of cases of RSV or norovirus on the DOH website.
The measles virus has caused infections in nine states this year, led by Texas where one child has died. South Dakota has not had a measles case in 2025, Clayton said.
"It appears COVID cases peaked in early January, but I can't say that we've peaked yet for influenza because we're at a very high level right now," he said. "And then on top of that you have pertussis and a lot of other respiratory viral infections."
Vaccination rates fall in South Dakota
The state population might be less prepared to fight viruses than in the past as flu vaccinations have fallen in recent years.
In the flu season of 2021-22, about 283,000 doses of influenza vaccine were administered compared to 233,000 this season, an 18% decline during a time the state population rose by 3.2%.
Vaccination rates are typically highest among older residents and lowest among those ages 6 months to 4 years, an age range where vaccine rates have slowed the most in the past few years.
The high rates of infectious diseases in South Dakota come at the same time as the appointment of U.S. Health and Human Services Secretary Robert Kennedy Jr., who has expressed anti-vaccination views in the past.
Clayton said the good news for South Dakotans is that the same tactics they can use to battle the flu also work to combat other infectious diseases.
Clayton recommended that people obtain available vaccinations, stay home if they are ill, cough or sneeze into an elbow or shirt sleeve, wash hands frequently and keep hands away from the nose and mouth.
"The one positive piece here is that a lot of the same actions can help prevent illness for a lot of those different pathogens," he said.
Basketball game canceled due to illnesses
Lance Witte, superintendent of the Lower Brule schools, said the district on the Lower Brule Indian Reservation in central South Dakota had so many student illnesses that a scheduled basketball game had to be canceled.
“On one of our teams, we had too many kids that were out sick, and our numbers weren’t going to be enough to play the game,” he said.
While Lower Brule schools have seen a variety of infectious disease cases this year, the primary cause of sickness has been the influenza A virus, Witte said. So far, none of the cases has been severe, he said.
“It’s kind of like cold symptoms, so the kids stay home or go to the clinic for treatment,” he said.
The district did extra cleaning during the high point of flu season and has since seen student illnesses subside since the winter cold snap in mid-February eased, Witte said.
Uptick in flu cases 'caught our attention'
The Chamberlain School District saw an uptick in student absences due to illness in January but has seen sicknesses taper off since then, said superintendent Justin Zajic.
The district saw several cases of influenza and the typical winter colds but had not reported a case of COVID-19 or whooping cough as of late February, he said.
“It caught our attention,” Zajic said. “But there’s a lot of little things we can do to stay ahead of it.”
That includes more frequent cleaning and disinfecting of surfaces in classrooms, gymnasiums and in activity rooms where students congregate, he said.
The district can also adjust the air intake on its heating system to introduce more outside air into classrooms to keep the air fresh and clean, he said.
Zajic said that many teachers and other staff members have children of their own, so when the flu or other diseases hit, it can force some employees to stay home to care for their own children.
When a child is out sick for a short or extended time frame, the district has systems in place to ensure learning continues. Nearly every middle or high school student in the district has a laptop they can use to review lessons at home. Students can also be tutored in study halls or after school so they don’t fall behind, he said.
Elementary children who miss class time meet with a specialist to determine if they fell behind and determine how they can quickly catch up, he said.
"We don’t ever want to leave a child behind, and we’re willing to put in the extra work to help them," Zajic said.
This story was produced by South Dakota News Watch, an independent, nonprofit organization. Read more stories and donate at sdnewswatch.org and sign up for an email to get stories when they're published. Contact Bart Pfankuch at bart.pfankuch@sdnewswatch.org.
