ALBANY, N.Y. (AP) — Health officials say a second wave of influenza has struck this spring and is putting more New Yorkers in the hospital now than in January.

The Albany Times Union reports that a different strain of flu is circulating than the one in midwinter, and people who already had the flu can get it again -- especially if they didn't get the vaccine.

The state Health Department says 648 New Yorkers were hospitalized with influenza during the first week of April. There were more than 2,500 confirmed cases of flu statewide that week.

Most flu cases earlier this season were H1N1, a type of influenza A. The latest cases are influenza B.

The Centers for Disease Control continues to recommend that people get flu shots if they haven't this year.

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