SACRAMENTO-

Four more cases of active tuberculosis were diagnosed within the last month, after extensive testing at a Sacramento County high school.

More than 450 people have been tested after a student at Grant Union High School tested positive for active TB in February. Family members, school staff and students were tested over the last couple of months, depending on their level of exposure to the student.

Sacramento County health officials told FOX40, four cases of the active form of the infection were diagnosed recently. One was diagnosed just last week.

Out of the hundreds who were tested, there were 120 positive test results for exposure, or latent TB. Health officials say testing positive for exposure to TB is not unusual.

Of those people, four had active TB and are undergoing treatment. Those four, FOX40 has learned, are students.

No more screenings are scheduled, however school officials at Grant Union High School are working to identify other students or faculty who may be at high risk of catching TB.

Tuberculosis is a bacterial disease that can spread through the air when there is repeated, prolonged, or close exposure to the infected individual.

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