On March 27, Hall Health officials sent an advisory e-mail alerting specific students to the news that one of their classmates had been diagnosed with active tuberculosis the day prior. The e-mail went out to all students who were enrolled in classes with the affected student, as Hall Health targeted them as having the highest probability of exposure.

Active tuberculosis is fairly rare; in 2008, the Seattle Health Department treated only 120 cases. As far as the UW population goes, Hall Heath Director David Dugdale said the last case encountered at Hall Health was about three years ago.

Tuberculosis is spread when a non-infected person breathes in what has been coughed up by an infected person. The tuberculosis bacteria are carried on tiny droplets from the lungs, which can then be inhaled by someone nearby.

“It’s quite difficult to actually get tuberculosis,” Dugdale said. “To get TB, or to have a high chance of getting TB from another person, you need to be in pretty prolonged contact in quite a closed space. So, for example, somebody who was walking by a person with TB and just walked by them and carried on, they wouldn’t get it.”

For students who shared classroom space with the infected individual, however, the risk of exposure is much higher. Hall Health advises these students be tested.

Students who come to Hall Health will undergo a skin test, which takes between five and 10 minutes and costs about $25. It involves a small shot that goes just under a person’s skin and creates a small bump. Individuals who take the test must then come back two or three days later for a reading of the test, which determines if it is a positive or negative test. Individuals are strongly encouraged to be retested three months later to see if the reading is the same.

A negative test is usually obvious right away, Dugdale said. The bump under the skin will disappear within a few hours of the shot being administered. Defining a positive test is more difficult, he said.

“It’s the way a person’s skin feels, more than how it looks,” Dugdale explained. “It could look red, for example, but feel completely normal, and that would still be a negative test.”

Dugdale added that the Hall Health staff is very experienced in interpreting skin tests, as they administer hundreds, if not thousands of them every year because all health sciences students have to take the test.

“This is not an unusual thing,” Dugdale said, referring to administering the test. “The unusual thing is that a student was actually diagnosed with active tuberculosis.”

Even though Dugdale said e-mails had been sent out to all affected students, some students that have been exposed say they have not received any notification and were not aware that they were at risk.

Dugdale stressed the fact that Hall Health strongly urges students who might have been exposed to come in for the skin test, and will continue to try to contact those students who are at the highest risk for exposure.

“If there’s a student who was in one of those classes and they haven’t gotten an e-mail, we want to know about that,” he said.

Reach reporter Molly Rosbach at news@dailyuw.com.