The percentage of people who went to the doctor with influenza-like illnesses has already reached 2.2 percent, an indicator that flu season has officially began, since only about 1 percent of doctor visits are for flu symptoms in the summer months.
Cases of flu have dominated the south and southeast. Five states – Alabama, Louisiana, Mississippi, Tennessee and Texas – have already reported high levels of flu activity.
According to the Center for Disease Control, 19 states have also reported local flu activity, up from eight states that reported local flu activity the previous week.
Adults and children should get their flu shots now, including babies older than six months, doctors say.
"Basic prevention is the most important thing [to avoid the flu]," said Christina Tran, Texas Health Harris Methodist Outpatient Center Burleson Emergency Department medical director. "Hand-washing and getting the flu vaccine. They should get a vaccine now. We started recommending it in October because it takes two weeks to take affect."
Symptoms include body aches, fevers and nausea, Tran said.
About a quarter of Americans gets the flu each year and an average of about 36,000 people die.
Though the flu season can start as early as October, the peak season is in January or later.
Flu season hit a peak last year in February.
So far, the vaccines manufactured for this season appear to be a good match for those strains of flu making people sick, according to reports.
About 120 million doses of flu vaccine are available this year, according to the CDC, and about 112 million people have already received their flu shots.
Tran said she's already seeing an increase in flu cases and says people should be aware of a potential wait for flu issues.
"We have seen a spike in the number of cases, even in Burleson," she said. "If they're feeling really sick, just expect a longer wait time in the ER."