DALLAS (CBSDFW.COM) – A Dallas Independent School District student diagnosed with tuberculosis has died. Health officials say the teenage girl died from an unrelated illness, but they’re still going to test her fellow classmates and teachers for TB.

The death of the 17-year-old student caught friends and classmates at North Dallas High School by surprise. “I couldn’t believe it,” one teenager said.

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Those who knew the high school senior say she had been sick since at least October; that’s when she stopped going to class. It wasn’t until December that doctors diagnosed the girl with tuberculosis. The realization came just days before she died from an unrelated illness.

The TB diagnosis concerns student Lejla Pracic. “Everybody is kinda freaking out, it’s like, because if I cough do I have it? Have I been having it and not knowing it,” she asked.

The letter sent out to parents this week, which warned of the potential spread of TB, has caused some alarm. “I feel kind of shocked, upset really,” parent Angelo Leija told CBS 11 News.

The timing of the notification is what bothers mother Melissa Mosqueva. “Oh, I’m very upset,” she said. “We just got letters this week. I think it [student diagnosis] happened sometime before winter break.”

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Officials with the Dallas County Health Department say they’ve just now became aware of the case and plan to visit the school later this month to offer free voluntary skin testing for TB on students and teachers.

“We’re not where people should be panicking… they should be concerned,” said the Director of Dallas County Health and Human Services, Zachary Thompson.

It’s that ‘concern’ that has plenty of student’s eager to be tested. When asked, “Are you getting tested?” one teen responded, “Yes. Definitely, definitely.”

Health department officials say students would have to have had prolonged exposure to the infected student, like being in enclosed environment with them, to be at high risk for infection. They say, realistically, very few people are at risk.

Anyone who wants to be tested right away can head to the main office of Dallas County Health and Human Services at 2377 North Stemmons Freeway.

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