Sickest Swine Flu Cases in Canada, Mexico Detailed

CHICAGO (AP) -- New reports on swine flu in Canada and Mexico describe rapidly worsening symptoms in the sickest patients.

Breathing problems that required intensive, lengthy care occurred shortly after the sickest patients were hospitalized.

Most survived. But the death rate in Mexican patients studied was much higher, 41 percent over two months. In the Canadian patients studied, the 90-day death rate was 17 percent.

The reports were published online Monday in the Chicago-based Journal of the American Medical Association.

They aren't a true snapshot on prevalence. But a JAMA editorial says they provide clues on what hospitals elsewhere may see as the winter flu season sets in.

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