December has brought more than colder weather. It has also seen flu figures continue to climb, according to data.
Houston Health Department Director Dr. Theresa Tran said the situation may actually be worse.
"We have not yet seen the results of the Christmas and holiday gatherings," Tran explained.
On Tuesday, the CDC released a map showing the flu situation nationwide. More than half of the states, including Texas, are reporting high or very high flu levels.
CDC estimates that there have been at least 7.5 million illnesses, 81,000 hospitalizations, and 3,100 deaths across the United States from flu this season so far.
Nationwide, CDC figures show more than a quarter of all samples being tested for the flu are coming back positive. That's up from 16 percent from mid-December, and eight percent from the week before.
The bulk of cases are linked to the new variant known as subclade K, according to thousands of samples sent to the CDC.
SEE ALSO: New flu variant 'super' K linked to spike in cases amid holiday gatherings
The numbers are even higher in Texas. Figures show that about a week ago, 32 percent of samples were positive.
That's nearly double from the week prior and more than three times higher than two weeks before that.
"This year, the trend is slightly higher than last year," Tran said. "So, I do anticipate that the trend is going to continue to rise."
An increase is also being found at schools, as the Houston Health Department tests wastewater samples from HISD locations.
A month ago, it found four schools had positive flu samples. Right before kids left for the holiday break, the number more than doubled to ten schools with positive samples.
"What I would recommend is for schools to encourage influenza vaccines for their children, their teachers, and their staff," Tran explained.
CDC experts say that the flu vaccine will still help reduce the risk of severe illness, including hospitalization and death.
There's still time to get the flu shot. Something experts say you'd want to get sooner rather than later because it can take a couple of weeks to get full protection.
According to the CDC, everyone over the age of six months is recommended to receive their annual flu shot.
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