RICHMOND, Texas – Nearly 700 students and faculty will be tested and re-tested for tuberculosis at George Bush High School near Richmond Thursday afternoon.

Four active cases were linked to the school back in May, and while officials are trying to contain the spread of the disease, not everyone has been eager to participate.

A total of 647 students and 27 faculty members were told to get tested on June 19. However, only about a third of them showed up. Of the 228 tests, 11 came back positive, though none of them had become active cases yet.

Fort Bend County Health and Human Services is asking those same students and staff to get tested again on Thursday, except for those who already tested positive. If those who received letters and emails asking them to get tested don’t show up, they won’t be allowed on campus when classes start on Aug. 22.

Tuberculosis is a bacterial disease which spreads by inhaling airborne, microscopic droplets or saliva that originate in the mouths of infected individuals. It is more difficult to contract that the common cold, but it is contagious.

“TB is a very serious disease and part of it is because it is hard to treat,” said Fort Bend County Health and Human Services deputy director Kaye Reynolds. “It can spread to all parts of the body and cause all sorts of issues including bone, organs, brain and so forth.”

There is no vaccination or preventative care available in the United States for tuberculosis.

TB tests used to be required for kids going to school in Texas, but that changed starting in the late 1980s due to a variety of reasons.

"You weigh that, and it's just not appropriate,” said Porfirio Villareal, Public Information Officer with the Houston Health Department. “The emotional costs, the financial costs when you have to go to the doctor, and that's a lot when you have false positives."

Health experts tell KHOU the most effective way to contain the spread to TB is the way they’re dealing with it in Fort Bend County: start with a small circle of individuals who were likely exposed to the disease, then expand it from there.

Health workers will conduct testing from noon-7 p.m. Thursday at George Bush High School, located at 6707 FM 1464 in Richmond.