Flu cases were on the rise in Wisconsin at the end of the year, according to the Wisconsin Department of Health Services.

Flu activity was labeled as "very high" the week of December 21 to December 27, which was up from "moderate" the week before.

"While most people associate respiratory illness with simply feeling under the weather for a day or two, these viruses can have serious consequences for people who are at higher risk, especially young children, older adults, and people who are pregnant or have chronic health conditions," said DHS Immunization Program Manager Dr. Stephanie Schauer, in a press release. "It takes about two weeks after getting a vaccine for your body to build immunity against the virus."

The increase in cases is typical this time of the year, with many people traveling and attending holiday parties.

Photo by the Wisconsin Department of Health Services.