Updated at: 07/03/2014 10:21 AM
(AP) SACRAMENTO, Calif. - SACRAMENTO, Calif. (AP) â€” A California high school is at the center of a tuberculosis outbreak linked to an infectious student who tested positive for active TB in February, county health officials said Wednesday.
Four more students at Grant Union High School in Sacramento have contracted active TB. Three related tuberculosis cases are considered an outbreak, Sacramento County Department of Health and Human Services spokeswoman Laura McCasland said.
Four relatives and friends of the student who initially tested positive have also contracted active TB â€” bringing the total to nine known cases.
Symptoms of active TB can include a persistent cough and fever. Active TB is contagious if it's in the lungs and accompanied by a cough, said Olivia Kasirye, the county's public health officer.
The four additional students â€” two of whom have TB in their lymph nodes â€” are not infectious, she said.
Kasirye said such an outbreak was not uncommon. The county sees about 90 active TB cases a year, though most of those are adults. She noted that no additional people have been found to be contagious.
"In a way, they are wrapping this up," McCasland said.
The four additional students are receiving treatment.
In all, a little more than 450 students and staff have been tested. They were considered at high risk because they used the same classrooms or adjacent classrooms as the student who was infectious, health officials said.
Of those, 116 have tested positive for TB, though the vast majority have been confirmed to be latent TB, which is dormant and doesn't produce symptoms. An additional thirty of the students in that group still need further testing to determine whether they have active TB, McCasland said.
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