PHOENIX -- State health officials say flu activity in Arizona has become widespread -- the highest categorization possible.
Influenza has been reported in all 15 counties, and the most prevalent strain is the 2009 H1N1 virus, according to the Arizona Department of Health Services.
Flu reports started early this season and have been increasing over the past few weeks, the department said. in Arizona, flu season typically peaks in February or March.
Of the 2,424 known cases this season, 824 were reported last week, the department said Wednesday.
Arizona is one 41 states that reported widespread flu activity last week.
While most people recover from the flu by getting a lot of rest and drinking plenty of fluids, others can have serious complications.
"Some of the symptoms of the flu are very similar to those of a cold," Dr. Cara Christ, Chief Medical Officer for the Department of Health Services, said in a statement. "Some people treat the flu like it's a cold and continue working. The truth is, influenza can be fatal."
Christ says anyone with flu-like symptoms should stay home to avoid spreading the virus.
"If you have a hard time breathing or have chest pains, you probably need to check with your doctor or get immediate help," she said.
Health officials also say it's not too late to get a flu shot, but even people who get vaccinated should wash their hands frequently and take other preventative measures.
"Obviously, the best thing you can do to protect yourself and others is to get vaccinated," said Dr. Bob England, Director of the Maricopa County Department of Public Health. "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."
A list of flu shot providers is available at www.stopthespreadaz.org or by calling Community Information and Referral at 211 from anywhere in the state. For more information about the flu, visit www.azdhs.gov/flu or contact your health care provider or local health department.