WASHINGTON -- Swine flu is causing unprecedented illness for so early in the fall -- including a worrisome count of child deaths -- and the government warned Friday that vaccine supplies will be even more scarce than expected through this month.
Federal health officials said 11 more children have died in the past week because of the virus.
The Centers for Disease Control and Prevention says about half of the child deaths since September have been among teenagers.
Manufacturer delays mean 28 million to 30 million doses, at most, will be divided around the country by the end of the month, not the 40 million-plus that states had been expecting. The new count from the CDC means anxiously awaited flu-shot clinics in some parts of the country may have to be postponed.
It also delays efforts to blunt increasing infections. Overall, what the CDC calls the 2009 H1N1 flu is causing widespread disease in 41 states.
Overall for the country, deaths from pneumonia and flulike illnesses have passed what the CDC considers an epidemic level. About 6 percent of all doctor visits are for flulike illnesses, levels not normally seen until later in the fall.
The CDC's Dr. Anne Schuchat said, "These are very sobering statistics."
This new strain is different from regular winter flu because it strikes the young far more than the old, and child deaths are drawing particular attention. Eighty-six children have died of swine flu in the United States since it burst on the scene last spring -- 43 of those deaths reported in September and early October alone, said Schuchat.
That's a startling number because in some past winters, the CDC has counted 40 or 50 child deaths for the entire flu season, she said, and no one knows how long this swine flu outbreak will last.
Half of those early fall child deaths are among teenagers, also surprising as preschoolers are thought to be most vulnerable.
Also in contrast to regular winter flu, swine flu sometimes can cause a very severe viral pneumonia in otherwise healthy young adults, the World Health Organization warned Friday.
Typically, influenza weakens people so they're vulnerable to bacterial pneumonia, especially those over age 65. But H1N1 can dive deeper into the lungs, in "small subsets" of patients who go into respiratory failure within days, said WHO medical officer Dr. Nikki Shindo.
"Do not delay the treatment," she said as the WHO ended a three-day meeting of 100 international flu specialists gathered in Washington.
Fortunately, most people recover from the new strain with simple at-home care, just as with the regular flu. While there aren't precise counts, states have reported more than 2,000 deaths from pneumonia or flulike illnesses to the CDC since Aug. 30. And Schuchat said other tracking systems show those deaths have reached the level that each year is used to declare an influenza epidemic, months early.
As of Wednesday, states had ordered 8 million of the 11.4 million doses of swine flu vaccine the government has ready to ship. A little more than half of the vaccine available is in shot form and the rest as a nasal spray. First in line for scarce H1N1 vaccine are supposed to be pregnant women, anyone ages 6 months to 24 years, health care workers and people under 65 with conditions that put them at higher flu risk.