The flu has killed at least 48 people across Pennsylvania. Cases are getting so serious that local hospitals are relying on a mini heart and lung machine to keep some patients alive.
"We literally drain the blood out of the right side of the patient's heart," said Dr. Raymond Singer, Lehigh Valley Health Network.
The device is called extra corporeal membrane oxygenation, or ECMO. It's a key survival tool during this brutal and deadly flu season.
"Allows lungs to heal up while we are giving antiviral, antibiotic therapy," Singer explained.
The device supplies a patient's blood with fresh oxygen, allowing those severely sick with the flu to breathe.
"This is a worst-case scenario," said Dr. Jeffrey Jahre, St. Luke's University Health Network, who noted that all four of his hospitals' ECMO machines are being used.
It's a situation Jahre said he's never seen, and the machine isn't just being used by older patients. Two are in their 20s; another is in his 30s.
"This is a very different flu season than we have seen in the past," Jahre said.
This year's dominant flu strain is the H1N1. Health officials said it targets younger and otherwise healthy adults.
Just since January, Singer said a dozen patients have had to use the hospital's ECMO.
"People that have severe flu have a 70 percent success rate. Keep in mind, they would die if not for this machine," he said.
Health officials said the machines are difficult to get and are in very high demand. They stress, more than ever, to get a flu shot because it's still not too late.