This flu season has been unusually difficult for adults under the age of 65 and, unfortunately, it has not yet ended, the Centers for Disease Control and Prevention (CDC) reported on Thursday. “The season is still ongoing,” Dr. Tom Frieden, CDC Director, stated in a press release. “If you haven’t yet, you should still get vaccinated." Younger- and middle-age adults between the ages of 18 and 64 represent nearly two thirds — 61 percent — of all flu hospitalizations. Comparatively, this group of adults represented only about 35 percent of all flu hospitalizations in the previous three seasons.

“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,” Frieden said. Vaccination has reduced a person’s risk of having to go to the doctor by about 60 percent across all ages. The currently circulating H1N1 virus, sometimes called the swine flu, originally emerged in 2009 and it is only this season that it has become predominant in the U.S. Symptoms include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills, and fatigue. For some people, vomiting and diarrhea may also occur, with respiratory symptoms minus a fever.

Surveillance data suggests flu activity is likely to continue for a number of weeks, especially where activity started late. States that saw earlier increases are now seeing decreases, while other states are seeing continued increases in activity. Last season, when influenza A (H3N2) viruses were the predominant circulating viruses, people 18 to 64 years accounted for only 35 percent of hospitalizations. People 25 years to 64 years of age have accounted for about 60 percent of flu deaths this season compared with 18 percent, 30 percent, and 47 percent for the three previous seasons, respectively. "It's important that everyone get vaccinated" said Dr. Frieden. “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."

Pregnant women, people with asthma, diabetes or heart disease, the morbidly obese, and those older than 65 or younger than 5 are at high risk for complications from the flu. In particular, those younger than 2 are susceptible.