She woke up one morning struggling to breathe. An emergency flight from Fresno brought her to Keck Hospital of USC, where she was put in an induced coma for three months. When she woke up she learned that her vital organs were failing.
"I was on a transplant list for lungs and kidneys," says Delgadillo.
Specialists at the hospital say that flu hits this nation harder than many people think.
"There were about 400,000 people that were admitted to the hospital with influenza. And it does affect young children and vulnerable adults, usually people over 65," said Dr. Anjali Mahoney.
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Yet Delgadillo, a 33-year old medical technician, had been an active mother of two with no pre-existing condition.
She said she missed getting her regular flu shot last year simply because she got busy.
Delgadillo said her father never got flu shots.
"My dad was very big on, 'Oh, it's a conspiracy -- the government,' or whatnot. But I think in general nobody ever thought that the flu could ever get this bad," said Delgadillo.
In this year's flu season, prevention is more critical than ever. Flu and COVID-19 cases threaten to overwhelm hospitals, creating a "twindemic."
It is all avoidable, said Mahoney because the U.S. has a plentiful supply of flu vaccine unlike other nations.
"If you go to some developing countries, you'll see where there aren't vaccines available and children are dying from vaccine preventable diseases. And adults are," said Mahoney.
With rehabilitation and treatment, Delgadillo made a dramatic comeback and is now off the transplant list.
She had been in the hospital for six months.
As for her father, who had mocked flu shots, she said he got one this year right away and is urging his friends and co-workers to do the same.