Dr. Brian Bruckner at Houston Methodist Hospital says in the past they would recommend the very young, very old, or the sick and infirm get the flu shot.
"Now with this severe form of called H1N1 or swine flu, we're suggesting that everybody get a flu shot. Because it can actually affect patients with no health conditions who are in the prime of their life at any age."
Bruckner is a cardiovascular surgeon and also the surgical director of the hospital's ECMO program, which is a life support intervention.
He says at Methodist, 40 patients have been admitted and 10 were placed on ECMO due to complications from H1N1.
For comparison, 22 were admitted last year, with only one life-threatening case.
"As a physician that treats the most extreme forms of flu complications, it's scary for me to see patients in the prime of their life in their 30s and 40s who are having severe complications. More than often these patients don't have any pre-existing medical conditions, working full-time and they contract the flu. And the course can be rapid, especially if they haven't had the flu shot."
The Centers for Disease Control and Prevention has stopped short of calling this season's flu outbreak an epidemic.
But the flu is categorized as widespread across the nation, and Texas is among the states with the highest rates of infection.