This news story reports that the “first, detailed analysis” of the H1N1 cases in Mexico included patients who:

- Were under 59 years of age.

- Did not fit any particular pattern of the kind public health officials look for.

- Were hospitalized with pneumonia.

- The doctors, whose report was published in The New England Journal of Medicine, noted that, of the patients who died,  “one contributing factor may have been delayed admission (to hospital) and a delay in starting the patient on the drug better known as Tamiflu (oseltamivir).

In some respects, the only pattern is that there is no pattern as of now, which is not uncommon in pandemics.

One may emerge.

Reuters

“Swine flu patients in Mexico were young and many were healthy before developing severe infections, doctors reported on Monday.

“The first detailed studies of the outbreak of a new strain of H1N1 influenza show the epidemic in Mexico resembled the early stages of other pandemics, and showed there is no way yet to predict who will become severely ill from the virus.”

…”Only eight had pre-existing medical conditions that might worsen their flu infection, they wrote — including high blood pressure, diabetes, asthma and sleep apnea. Seven died — all of multiple organ failure.

The doctors said 90 percent of the seriously ill patients were under 50 – in contrast to seasonal influenza, which causes mostly mild illness in people under the age of 65.

“Most of our patients were young to middle-aged and had previously been healthy,” they wrote in their report, published in the New England Journal of Medicine.

“One contributing factor for death in our patients may have been delayed admission and delayed initiation of oseltamivir.”

Source: Reuters, June 29, 2009

Citation: New England Journal of Medicine, Online Edition, June 29, 2009 (10.1056/NEJMoa0904252)