A senior technician holds collected blood samples. (credit: Rodger Bosch/AFP/Getty Images)

DENTON (CBSDFW.COM) – Tuberculosis testing started Tuesday for some 200 students in the Denton Independent School District.

A student, who transferred to the Denton ISD from Ennis High School, fell ill last week and had to be hospitalized. CBSDFW.COM first reported Wednesday that the 16-year-old’s initial TB skin test was positive for the contagious or active form of the disease. As a result, anyone who spent six hours or more with him would have to be tested for TB.

As we have reported, dozens of Ennis ISD students have tested positive for latent, or non-contagious, tuberculosis in recent weeks.

Student Alex Johnson is among the teens that will be tested.  Johnson said the infected student from Ennis rode his school bus, but he had limited contact for them.

Asked whether he was nervous about the test Johnson said, “A little bit… but I’m just gonna get it over with. I’m not scared or anything.”

For the most part, Denton parents said they’re not concerned about spread of the disease and credit the response of Denton ISD officials.

“I received two phone calls and a letter was brought in, so I was well informed,” said parent Christine Collins.

TB is a contagious, airborne bacterial disease that generally attacks the lungs but can also infect the spine, brain, kidney and other organs.

A latent TB infection is not contagious. Those who become ill with TB have active TB germs and are considered contagious.