Four months into the flu season, at least 22 million U.S. residents have contracted influenza – and possibly as many as 31 million people, according to the Centers for Disease Control and Prevention (CDC). Of those afflicted,about 210,000 have been hospitalized and at least 12,000 have died of the flu, including 78 children as of Feb. 7.

The rate of infection among children and young adults so far this flu season, which officially began Oct. 1, has been higher than normal, the CDC noted in a report this month. All states have been hit with the flu, according to CDC experts who track its spread, with 47 states now described as having a high level of flu activity.

To keep from catching the flu, which is a highly contagious respiratory illness caused by a virus, people are advised to take simple precautions, such as washing your hands often to reduce the chance of spreading germs and staying away from others who are sick. The best way, however, is to get a flu shot each year, which the CDC recommends for nearly everyone 6 months and older.

So far this flu season, more than 173 million doses of the flu vaccine have been administered. People are always encouraged to get vaccinated before the flu season starts, but the CDC says even now it is still not too late. Although the season usually winds down in March, risk sometimes remains until May.