FastMed Urgent Care medical director Sean Wang says that the flu is something to take seriously, especially this year.

"I have personally seen many people very sick from the flu," Wang said. "Some of them have died from the flu."

Less than half of all Texans get their flu shot, around 43.6 percent.

"It can decrease your immune system and cause super-infections, such as pneumonia and other infections that can cause a high mortality rate," he said.

Children and the elderly are the most at-risk. Dr. Sky Izaddoost says that children need to start vaccinations at 6 months old.

"Kids that are perfectly healthy can still have serious problems with the flu," she said.

The CDC says that the flu results in more than 200,000 hospitalizations and more than 23,000 deaths per year.

Doctors say that a simple shot can mean the difference between life and death.

"The earlier the better," Wang said. "Because it does take two weeks for it to start working."