Half of those hospitalised with the new H1N1 virus are under 25, a clear illustration that the pandemic is affecting the young disproportionately, US health officials said.
They said reports from 27 US states show 53% of people sick enough to be hospitalised with H1N1 flu are under the age of 25, with only 7% of hospitalisations among people 65 and older.
"This is really, really different from what we see with seasonal flu," the CDC's Dr Anne Schuchat told reporters. "With seasonal flu, about 60% of hospitalisations occur in people 65 and over." She stressed the report was incomplete but said if anything, it was underestimating the extent of the pandemic.
Young people dying
And an analysis of 292 deaths from 28 states showed that younger people than usual are also dying, she said.
"Almost a quarter of deaths are occurring in young people under the age of 25. Specifically, 23.6% of the deaths are in that age group. About 65% of the deaths are in people 25 to 64 years of age," Schuchat said.
Just 12% of deaths were among people over 65. In a normal year, 90% of those who die from flu are over 65.
With cooler weather, other viruses and infections are showing up, making the picture confusing.
Schuchat said influenza is being diagnosed in about 30% of all people showing up with "influenza-like illness," symptoms that include cough, sore throat, fever and aches.
Almost all influenza is turning out to be H1N1 rather than seasonal influenza and Schuchat said the tests often miss cases of H1N1, so the percentage may be higher.
Ordinary colds, group A streptococcus, which causes "strep throat", and other infections can cause similar symptoms. - (Maggie Fox/Reuters Health, October 2009)
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