INDIANAPOLIS -- A rare strain of Tuberculosis has been found at an Indianapolis homeless shelter, threatening residents and aid workers, health officials said.

The TB strain, designated as IN-074, is so rare that it has only been identified in Marion County, health department Director Dr. Virginia Caine told 6News' Rick Hightower.

The eight cases were all found in homeless men between the ages of 32 and 64 in a shelter that Caine would not identify.

During their investigation, health officials found a total of 58 cases of TB among homeless men at various shelters, but the men who contracted the rare strain did not have any symptoms, Caine said.

"I think the general population is always at risk when you have an individual out there who may have tuberculosis, they may have to go into a grocery store," she said.

Some area shelter workers said they were worried about the situation as well.

"It definitely concerns us," said Charles Haenlein, CEO of Helping Homeless Veterans and Families shelter downtown. "In fact, we're waiting for some type of information from the health department now as to what we need to do in addition to what we're already doing to combat this."

He said everyone who enters the shelter goes through a rigorous health screening process, and that employees must take a TB test twice a year.

Symptoms of TB include cough, fever, chills, weight loss, night sweats and fatigue.