Students at Northeast High School have a lot of questions after the 14 fellow classmates tested positive.
"A lot of people are scared, nervous, want to know who the person was, is the person still in school, are the people infected still in school?" said student Netanya Davis.
But TB expert Dr. David Schlossberg of the Philadelphia Health Department wants people to understand what that positive test means.
"It is an important distinction between TB infection and TB disease," Dr. Schlossberg said.
Tuberculosis is first tested for with a PPD skin test, the same test given to 80 students at Northeast High School had.
A small amount of fluid is injected, then the area is reexamined in two to three days.
"If there's a reaction that's when you'd see it," said Dr. Schlossberg.
If the skin test is positive Dr. Schlossberg says it doesn't mean the person has the active disease but it can point to a latent TB infection.
"Latent TB, by definition, has no symptoms and it's not transmissable," he said.
That means kids at Northeast High School can't spread it to other kids. But, some will need a chest x-ray and may need medication to prevent active TB from developing.
There's no definitive way to tell how someone got infected but it is important that they are treated.
If someone does need treatment, even for a latent infection, that could mean taking medication for up to nine months.
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