This flu season alone, 397 people have been hospitalized with influenza-associated illnesses in Wisconsin, many of whom are young adults.

According to the Centers for Disease Control and Prevention, 67 percent of those hospitalized are between the ages of 18-64.

“Young adults and middle-aged adults nationwide are getting hit harder by the kind of flu going around right now,” Cheryl Robinson, Public Health Madison and Dane County spokesperson, said.

Craig Roberts, University Health Services spokesperson, said no valid explanation exists as to why influenza is hitting certain age groups so hard this season. He said the flu is likely hitting those who have not had a vaccination in the past few years.

The type of flu virus sweeping the nation is scientifically known as influenza A H1N1, Robinson said. Yet, she said this is only one kind of flu, and another flu virus will likely spread once H1N1 subsides.

Roberts said H1N1 has been circulating for roughly five years. The virus first showed up during the flu season of 2009, he said.

“Usually we expect the flu to hit young people like babies or old people or people with chronic illness,” she said.

Robinson said people usually do not get flu shots because they do not think they need them. She said if people have not been vaccinated in the past and have remained healthy, they are less likely to do so in the future.

She added this season, many people without vaccinations have become quite ill. Some victims have even been hospitalized in intensive care units as a result of the virus, she said.

Roberts said there have been very few incidences of influenza in the student population aside from a slight peak of cases during the last week of classes. However, given the prevalence of the virus nationwide, he said UHS is expecting and prepared to deal with H1N1 spreading as students return to campus.

Robinson said the medical school is also providing flu shots for uninsured adults and children. Anyone who is uninsured and would like to receive a flu vaccination can call 608-266-4821 to make an appointment. She said the department has 10 clinics in four different locations.

“The flu can keep going into the spring,” Robinson said. “This is a good time to get a flu shot and keep yourself healthy throughout the season.”

For University of Wisconsin students, Roberts said UHS will also provide flu shots during the entire flu season. He said it is “never too late” to get a flu shot. This week, UHS is offering walk in hours for flu shots on Tuesday through Friday from 9 a.m. to 4:30 p.m.

Robinson said Public Health Madison is advocating strongly for flu vaccinations this season because people who believe they are the healthiest are becoming infected at higher rates.

“Protection from the flu shot is only temporary, it lasts about six months, so that is why you have to get another one every year,” Roberts said. “Plus the flu virus changes a little bit every year, so last year’s vaccine may not protect against this year’s virus.”

Correction: Craig Robert’s name was previously incorrectly reported as Chris Roberts. We regret the error.