via Kevin MD

Young, otherwise healthy people who contract H1N1 flu can rapidly deteriorate into a critically ill state in a manner that is eerily reminiscent of the 1918 Spanish flu pandemic, according to research published in the November 4 issue of the Journal of the American Medical Association

Researchers from St. Boniface Hospital in Winnipeg observed 168 patients who contracted confirmed or probable cases of H1N1 flu and who became so critically ill they required care in hospital intensive care units (ICUs).

The average age of the patients was 32 years, and 30% were children. The patients experienced symptoms for an average of four days before being hospitalized and then rapidly deteriorated, requiring ICU care an average of a day or two later. These patients commonly experienced shock and multi-system organ failure, and over 80% required mechanical ventilation, usually for prolonged periods. Several other lung rescue measures were required to keep them alive. Ninety days after the onset of critical illness, just under 83% of patients were still alive.

The numbers behind young, healthy people dying from H1N1 flu