PHOENIX -- Flu season is picking up across the state.
According to the Arizona Department of Health Services, flu activity hit "widespread" status this week -- the highest category possible -- with influenza reported in all 15 counties.
"Last week we had an additional 825 cases, bringing us to 2,424 this season," said Dr. Cara Christ, chief medical officer for the AZDHS.
Most of the flu cases across the state and similarly across the nation have been diagnosed at H1N1, the same strain that caused the swine flu scare in 2009.
Christ said the end of January is generally the peak of flu season. However it's normal for lab-confirmed cases of the flu to increase through March.
"If you suddenly feel sick, tired and begin coughing and sneezing, take care of yourself," she said. "Stay home and don't spread the virus to others. If you have a hard time breathing or have chest pains, you probably need to check with your doctor or get immediate help."
Some hospitals such as Phoenix Children's Hospital and Banner Hospitals are restricting access to visitors who may exhibit symptoms of the flu. Christ said hospitals take precautions to protect their patients by limiting the amount of people bringing in influenza.
"It's people with pre-existing conditions with other health conditions that really get infected with influenza."
If you still haven't gotten vaccinated, it's not too late.
"With our community reaching widespread status, this means that flu is circulating and even if you get vaccinated today, it will take two to three weeks to build up antibodies," said Dr. Bob England, director of the Maricopa County Department of Public Health.
Forty other states reported widespread flu activity last week. The Centers for Disease Control and Prevention influenza season begins in October and carries through September.
A list of flu shot providers is available at stopthespreadaz.org or by calling Community Information and Referral at 211 from anywhere in the state.
For more information about influenza, go to azdhs.gov/flu or contact your health care provider or local health department.