This article was updated at 7 a.m. July 23.
On Monday, Fairfax County Health Department officials announced plans to expand its investigation of tuberculosis cases initiated at Robert E. Lee High School. In June, the health department reported three people within the Lee High School community had been identified as having active TB. One person was diagnosed in December 2012, and two were diagnosed in June. One of the June cases was linked to the December diagnosis.
As a result of the three cases, the department and Fairfax County Public Schools mailed more than 400 letters to students and faculty alerting them to their possible exposure. About 60 percent of these individuals were tested for TB at free clinics held at Lee High School earlier in the summer.
In the wake of these initial TB screenings, the health department announced Monday it had mailed an additional 1,900 letters to school community members, increasing the scope of their investigation to all students, faculty and support staff in the school.
“The test results show a higher than expected skin-test positivity rate. The skin-test shows latent TB infection,” health department spokesman Glen Barbour said. “Latent is not active. Latent TB is not contagious. You’ve just been exposed to the germs.”
According to the Centers for Disease Control and Prevention, about 10 percent of latent TB cases become active TB. Symptoms of active TB include coughing that lasts three weeks or more, chest pains, coughing up blood or sputum, weakness or fatigue, weight loss and lack of appetite, chills, fever and night sweats. The health department says TB is preventable and curable if treated.
“We want everyone at the school who has not been tested to take advantage of the special clinics and get tested,” said Director of Health Gloria Addo-Ayensu during a press conference Monday afternoon. “Our goal is to get as many people tested as possible before the school year starts.”
So far only 60 percent of those identified under the first round of investigation have been tested in county-run special clinics at Lee High School. Additional clinic hours have been scheduled.
About 4 percent of the total U.S. population has latent TB, said Addo-Ayensu. This percentage is higher among foreign-born residents than the U.S.-born population, which equals less than 1 percent of the latent TB rate. Latent TB rates are also higher among those who travel internationally and may be exposed to higher concentrations of TB-positive populations. During the county health department’s investigation, the number of U.S.-born Lee High School community members testing positive for latent TB was higher than county officials had expected.
“This was significantly higher than what we would have expected for the U.S.-born in this area,” Addo-Ayensu said. “There is no ongoing transmission… The vast majority of the Lee High School community was not at risk of exposure of TB… The goal of our TB investigations is to first of all determine who has been exposed…and prevent future exposure of TB.”
Barbour said the health department does not yet have an estimate available on the cost of TB testing held because of the Lee High School cases. Costs are being tracked, but no official figure has been estimated as the TB investigation is ongoing.
For more information about the TB investigation, go to www.fairfaxcounty.gov/hd/hdnews/2013-tb-investigation.htm