Health officials are asking roughly 430 students and teachers at a Virginia high school to undergo tuberculosis testing, fearing that they may have been exposed to the disease in the wake of three confirmed diagnoses. The first diagnosis came back in December, but officials really got worried this month, when two more people from the same school came down with the disease, WTOP reports. In all three cases, the patients had the active, contagious form of TB.
Now the Fairfax County Health Department is launching an investigation, and trying to identify anyone who may have been in close contact with the patients. The county's health director initially said that the two diagnosed this month were students, but then backed off from that statement, refusing to confirm whether they were staff members or students. Fairfax County is no stranger to TB—it had about 90 cases last year, the Washington Post reports—but most cases originated overseas, and fewer than 30 cases across the state involved people under age 24.