DENVER – In a packed emergency room, Elijah Ibarra fussed and cried as his father gently slipped a purple elastic band around the 2-year-old's head to hold an oxygen mask in place.
The little boy settled into a restless sleep on the examining table, his long eyelashes occasionally fluttering as his worried parents listened to whispered instructions from a doctor: Give him fluids. Watch his breathing. Check his temperature. Bring him back if he gets worse.
"He was throwing up, and I brought him in right away," said the boy's mother, Naomi Ibarra.
One of the harshest flu (search) seasons in years has swept across Colorado, sending jittery parents rushing to ERs and clinics with feverish children. Within the past month, more than 6,300 people have been infected and at least six have died.
All the dead were under 16 years old, raising fears that this year's flu strain is especially deadly in children. Experts say it is too early to know for sure.
Dr. Tim Uyeki, medical epidemiologist for the Centers for Disease Control and Prevention (search), said the number of children getting seriously ill and dying from the flu worries the agency. Typically, he said, "there may be a lot of illness among children, but deaths usually occur among elderly people," and so far the agency has not had reports of many elderly deaths.
Doctors said two children who died in Colorado had medical conditions that made the flu more dangerous.
"It's the most widespread, one of the hardest-hitting (seasons) in terms of the severity and the duration of the illness, and it all happened so fast," said Dr. Mary Maguire, a pediatrician at the Children's Medical Center in Denver. "It just happened overnight with a degree that I haven't seen before."
The flu also is being blamed for three deaths in Texas and one each in Oklahoma and New Mexico.
In all of last year's cold season in Colorado, only two child flu deaths were reported to the state. None were reported the previous year and two in the 2000-01 season.
Colorado is one of 13 states with a widespread flu outbreak, the highest designation given by the CDC. The others are Alaska, Arkansas, Idaho, Nebraska, Nevada, New Mexico, Pennsylvania, Tennessee, Texas, Utah, Washington and Wyoming.
"I don't recall it being this bad ever -- and especially in kids," said Craig Gilliam, infection control expert at Arkansas Children's Hospital (search) in Little Rock, Ark.
Typically the hospital has about 25 to 30 positive flu cultures during November; last month the hospital had 265 positives. About 45 percent of the cases have been children ages 1 to 5; 40 percent have been school-age children, ages 5 to 15.
The seemingly high number of deaths among children could be due in part to better reporting as well as a real increase, said Dr. William Schaffner, chairman of Vanderbilt Medical Center's department of preventive medicine in Nashville, Tenn.
In the very young and the elderly, flu can cause organ damage; during a bad flu season, deaths from kidney, liver and heart disease rise. An estimated 36,000 Americans die from the flu every year. Health officials do not know how many children die because states do not require doctors to report influenza cases.
Even before this year's deaths, there were signs this could be an especially bad flu season. Some parts of the country were hit hard a month earlier than usual, and doctors are seeing the A-Fujian-H3N2 strain, part of a class of flu viruses that caused severe outbreaks in the United States in the 1990s.
Dr. Chris Nevin-Woods, health director in Colorado's Pueblo County, said the severity of the outbreak could be because this year's vaccine did not cover the A-Fujian-H3N2 strain.
"That doesn't mean it won't cross-protect, but it does mean it's not as effective," Nevin-Woods said.
In addition, the nation's two manufacturers of flu shots said Friday they have run out of vaccine and will not be able to meet this year's surge in demand. Ordinarily, the 80 million doses made by Chiron and Aventis Pasteur would be enough to take care of U.S. demand.
Thousands of people across Colorado have swamped hospitals and clinics for flu shots. At least four schools closed because of flu-related absences. Day-care centers are doggedly disinfecting door handles and washing children's hands. Hospitals have strict new limits on visitors. And over-the-counter remedies are flying off pharmacy shelves.
"It's not tapering off," said Tom Starr, a pharmacist in suburban Wheat Ridge. "We're seeing a line of sick adults and kids."
Last month, Eve Blaney was sitting in a Denver hospital emergency room when her 17-month old daughter, Madison, went into respiratory arrest while being treated for the flu.
"Madison looked at me, took one last breath, her lips turned blue and she stopped breathing for 3 minutes," she said. "I thought I was going to lose her, and I was so scared. I kept praying, I fell to my knees."
The little girl spent one day in intensive care and another in the hospital before coming home. She has made a full recovery.
Blaney is convinced that her cousin, Donald Regan, a New York firefighter killed in the World Trade Center collapse, was watching over Madison. The little girl's middle name is Regan.
"I was thinking Donnie, just rescue one more person," Blaney said.
Down the hall from Elijah at Children's Hospital, Sherry Torres tried to comfort her 3-year-old son, John. The boy, who had been vomiting and had a fever, body aches and sore throat, sucked a red Popsicle between cries of pain.
"I'm pretty terrified, to be honest," Torres said.