HOUSTON -

The flu has been spreading fiercely across the United States, with more than half of states reporting widespread activity.

At the Nueva Casa De Amigos Health Center, 1809 North Main, officials have been busy administering flu shots. Doctors and nurses have about a thousand flu vaccinations, but they said if they run out, they will just ask for more.

"So far, there's a very good supply," said Porfirio Villarreal, public information officer for the city Of Houston's Health Department. "If we run out, we'll just order other shipments."

Those shipments would come from the state.

Experts advise the best way to protect yourself from the flu is, in fact, the flu shot. They said it is the best shot for fighting the flu in years.

"What the scientists are saying is the shot is 90 percent effective," said Villarreal. "The vaccine is a good match. It's matched with three of the most common viruses."

If you got the flu shot back in the fall, it is the same vaccine they are giving out now.

"It's still good now," said Ana Guien, a registered nurse supervisor. "It protects you from June 2012 to June 2013."

Doctors at Texas Children's Hospital said flu cases in Houston were up in November and December but dropped a bit in early January.

"We are predicting and planning for increase volumes next week or so as school gets back into session," Dr. Kay Leaming-Van Zandt said.

Doctors at The Methodist Hospital said they have seen two to three times the normal level of patients in the emergency room with flu symptoms.

The numbers of flu cases are up across the country, according to the latest weekly flu report from the Centers for Disease Control and Prevention. The flu report showed widespread flu cases in more than 40 states, including Texas.

The Texas Department of State Health Services reported three children died after getting the flu. Two children were from Southeast Texas and the other North Texas.

Doctors strongly recommend there is still time to protect your family from flu.

"There are so many places in Houston and the surrounding areas that are still offering both the flu mist and the flu shots," said Dr. Leaming-Van Zandt.

Texas Children's Hospital employee Jenn Jacome got her flu shot. Her extended family did not.

"My sister is home sick. My mother is home sick and my other sister's boyfriend in town for my brother's wedding is sick," said Jacome. "Timing could not be worse with my brother's wedding on Saturday, and we have relatives coming in today to stay at our house for the wedding on Saturday."