The flu season is barely under way, but a sharp rise in the number of H1N1 swine flu cases is already stretching scarce resources at many hospitals.
At the University of California, Davis, Medical Center, in Sacramento, there's been a four-fold increase in H1N1 cases in just three weeks.
One of those cases is 4-year-old Ferris Labban, who is fighting off a nasty infection.
"Ferris basically went from having the typical flu to a complete collapse of lung and pneumonia in a week," Ferris' mother Wendy Labban said. "This H1N1 is completely aggressive, the way it affects our child's body was unbelievable."
Due to the severity of Ferris' condition, doctors inserted a tube into his left lung to drain it of fluid.
"The care that he got here was around the clock," Labban told "Nightline."
Round-the-clock treatment for H1N1 patients is typical in the pediatric intensive care unit. Nearly half the kids admitted to hospitals with a case of the H1N1 virus wind up in intensive care. No part of the hospital is under more strain than pediatrics.
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"We're scared about H1N1 and how severe it can be and the resources it needs and the toll it is going to take on all of our staff," said Dr. Mac Wayment, a specialist in pediatric critical care.
Two weeks ago in the same hospital room where Ferris was being treated, "Nightline" met Benjamin Oback, who was also infected with a severe case of the H1N1 virus. Then in critical condition, the 10-year-old was fighting for every breath. His parents prayed and stood vigil.
"I feel like part of my soul has been crushed," Benjamin's father Eric Oback told "Nightline." "It's the worst imaginable feeling to see your kid fall that quickly and to be that ill. The night that he went to the emergency room was the scariest moment I've had in my entire life."
Benjamin's mother, Julie Oback, said her son appeared to have a minor case of the flu earlier this month, but quickly "became unresponsive" and was rushed to the hospital.
Like so many of these critical pediatric cases, Benjamin's illness required coordinated care from every corner of the hospital.
"For Benjamin it required all the different services in the children's hospital," said Dr. Laura Hufford, a pediatrician treating Benjamin. "He needed all the physicians and the nurses there. He needed respiratory therapy, physical therapist. ... So really, he kind of uses all units of our hospital."
Benjamin has now moved out of intensive care into the general pediatric wing, where he is slowly regaining his strength.
"Benjamin is doing well, has begun the road to recovery from his illness," Hufford said. "He's stopped having fevers, been able to get out bed, and he has started eating again."
While Benjamin's prognosis is good, the pediatric wing has a heavy caseload. Hufford and her team are dealing with eight confirmed cases of H1N1; that's up from three last week, but another 18 kids have to be checked out.
In each one of these cases, Hufford must put on a gown, gloves, and a special mask to protect herself and the patient from contracting infections.
"I have to use different ones for each patient. It's a lot of masks a lot of gowns," she said. "We probably have to change over 40 times a day, I would say."
Ferris' condition is improving. He must wait for a bed to open up in the pediatric unit, which is full of sick kids.