The student attends the Science and Discovery High School in Chester and came in contact with someone who had TB. School officials sent letters and consent forms to the parents of nearly 300 students. 200 came back granting permission for the teens to get skin scratch tests for TB. 20 of them tested positive for what is called latent TB; this means they carry the germ, but don't have an active case
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"A lot of people have it, most people never know it and I would say, most people don't go on to develop the disease," Phyllis Britz, R.N. of the Pennsylvania Health Department said.
The Pa. Health Department says 5 to 10 percent of the population carries the latent TB. The students who test positive will have follow up chest x-rays and its recommended they take the drug Isoniazid.
"The TB germ which is basically sleeping inside them, it can be killed with Isoniazid," Britz said.
TB is a very contagious and serious bacterial disease transmitted through the air by a sneeze or cough.
Dr. Joyce Wells is the acting superintendent of schools.
"The Department of Health insured us that the environment was safe cause our students are very important to us and our community is very important to us and we want to make sure we safeguard them" Dr. Wells said.
Those with latent TB don't feel sick or have symptoms and are not contagious.
School and health officials say if other students from other schools are concerned they should check with their doctor or the state health department to get tested.