The search is on for 27 people who may have been exposed to tuberculosis while traveling on a Greyhound bus.

Canadian public health officials say there’s a “moderate risk” the passengers contracted the disease during a trip from Toronto to Windsor on Aug. 31, ctv.ca reported.

Officials fear a passenger who was sick with TB may have infected other passengers by openly coughing on the bus. The passenger, identified as a woman with a Canadian passport, was detained by American custom officials at the border between Windsor and Detroit, Mich., the television station said on its Web site.

The good news is that the woman’s symptoms are not serious and passengers should not panic, according to Ontario's Chief Medical Officer of Health Dr. David Williams.

"The risk to the public is not a high one,” he said. “But we need to go the extra mile and make sure to contact those people the best we can.”

TB is a bacterial infection caused by a germ called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but they can also damage other parts of the body, according to the Centers for Disease Control and Prevention. It spreads through the air when a person with TB of the lungs or throat coughs, sneezes or talks. If not treated properly, TB can be deadly.

Symptoms include:

— A bad cough that lasts 3 weeks or longer

— Weight loss

— Coughing up blood or mucus

— Weakness or fatigue

— Fever and chills

— Night sweats

The Greyhound reached the U.S. border with 42 passengers on board.

Health officials want to get hold of the 27 passengers who got off the bus in Windsor so they can be tested for TB.

The remaining 15 passengers are being monitored by health officials in the U.S. and Ontario, according to the report.

Click here to read more from ctv.ca.