HARRISBURG, Pa. (AP) — Flu season appears to be in full swing in Pennsylvania, with health officials reporting outbreaks in at least half the regions of the state.

The state Health Department confirms nearly 1,200 cases of influenza between Sept. 29 and Dec. 21.

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The hardest-hit areas are in western Pennsylvania, led by Allegheny and Blair counties.

Flu is usually the worst in January or February, although last year the illness hit the U.S. very hard in early December.

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According to the Centers for Disease Control and Prevention, last year’s flu season landed about 381,000 people in the hospital nationwide. That’s the most since at least 2005.

A contributing factor: The flu vaccine was only 51 percent effective overall.

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