CEDAR HILL, Texas - Dallas County health officials say there could be even more cases of mumps at Cedar Hill High School before the outbreak is over.
The number of cases is now up to 27 among students and staff, and they're planning a health clinic at school to try and contain the spread by offering free booster shots.
All of the diagnosed students were vaccinated, but Dallas County Health and Human Services said the vaccine is only 88 percent effective after two doses.
Antonio Edwards says he quickly found out his daughter wasn't exaggerating about a mumps outbreak when a letter went home to parents and news crews descended on the school.
"That's a lot of people, especially in a building like that confined with mumps going around," he said.
On top of the 27 cases at Cedar Hill High School, health officials say there are an additional six unrelated cases in Dallas and Mesquite.
The health department is now recommending that everyone at the school get a third booster dose of the MMR vaccine. Workers will set up a clinic at the school Friday to offer students and staff free booster shots. At least 50 to 100 students are expected to receive it.
"Of course there could be additional students impacted because of the close contact that they may have had with those who have already had the mumps," said Zach Thompson, the Dallas County health director. "And so that's why the vaccination of offering the third dose is so critical."
Mumps can spread as an infected person coughs, sneezes or shares food. Symptoms are similar to the flu and include fever, headaches, swollen salivary glands, fatigue, muscle aches and a loss of appetite.
"When you have kids who play together at sports events and activities, of course there could be more cases," Thompson said. "But parents should watch and observe their kids and if they have any of those symptoms and make sure that you check in with your primary physician."
In the meantime, the high school is undergoing heavy disinfecting.
"I don't want to send her to a place where she could get real ill," Edwards said. "I'm concerned. My wife's concerned, but we don't want to do anything premature by taking her out."
District officials say they've been working with Dallas county and following their guidelines but have not discussed closing down the school.
Cedar Hill High School said it called parents after the first few cases were confirmed last month and the campus was thoroughly cleaned.