This flu season was believed to have hit younger and middle-aged adults harder than usual. 

The Centers for Disease Control and Prevention (CDC) reported that individuals between the ages of 18 and 64 made up 61 percent of all flu-related hospitalizations this year, a PR Newswire news release reported. Last season this age group made up only about 35 percent of influenza hospitalizations. 

"Flu hospitalizations and deaths in people younger- and middle-aged adults is a sad and difficult reminder that flu can be serious for anyone, not just the very young and old; and that everyone should be vaccinated," CDC Director Tom Frieden, M.D., M.P.H, said in the news release. "The good news is that this season's vaccine is doing its job, protecting people across all age groups."

A recent analysis predicts in many regions flu season will continue for several weeks, especially in areas where the infection hit later than average.

The people who are sternly affected by the virus every year depend on the strain; the H1N1 virus which is currently making its rounds caused a pandemic in younger people in 2009. 

"Younger people may feel that influenza is not a threat to them, but this season underscores that flu can be a serious disease for anyone,"Dr. Frieden said. "It's important that everyone get vaccinated. It's also important to remember that some people who get vaccinated may still get sick, and we need to use our second line of defense against flu: antiviral drugs to treat flu illness. People at high risk of complications should seek treatment if they get a flu-like illness. Their doctors may prescribe antiviral drugs if it looks like they have influenza."

Those most at risk for the flu are people suffering from "asthma, diabetes, or heart disease" as well as pregnant women, people over 65, and children younger than five.