Influenza activity is elevated this season, the Arizona Department of Health Services says, with three strains primarily affecting middle-age and elderly people. (Photo by Blake Hemmel/Cronkite News)
Widespread flu activity has made the 2017-18 season one of the worst in years, especially in Arizona. Every county in the state has confirmed an influenza case this season, and about 19,000 more Arizonans have been infected compared with last year. The middle-aged and elderly in particular are being affected more than normal.
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