State health officials say Illinois flu activity continues to be high in a season where the virus struck earlier than usual.

Illinois Department of Public Health spokeswoman Melaney Arnold said Friday that 534 people have been admitted to hospital intensive care units with the flu this season and 58 have died.

She says all but 1 of the people who died were age 50 or older.

This year's main flu strain tends to make people sicker, and public health officials continue to encourage people to get vaccinated.

Flu typically includes a fever and respiratory problems such as cough, sore throat, runny or stuffy nose. It can be accompanied by head and body aches and fatigue. Most people recover in one to two weeks, but some develop complications such as pneumonia.