A second person in Cape Breton has been diagnosed with active tuberculosis.

Lesley Mulcahy, a spokesperson for Nova Scotia Health Authority, said the latest case is linked to one diagnosed in late 2017.

"They are not separate cases," she said. "One likely contracted from the other."

Tuberculosis is contagious and is transmitted through the air. It generally affects the lungs and was a leading cause of death in the early 20th century.

Infection usually requires prolonged, close contact with an infected person.

The health authority said the risk to others who were in contact with the two Cape Breton tuberculosis patients is low.

However, the agency is following up with people who may have been exposed to tuberculosis during an in-patient stay at the Cape Breton Regional Hospital while visiting a patient or during a medical appointment during a three-day period in September.

Still testing

CBC first reported on Jan. 27 that, as a precaution, about 80 staff at the Cape Breton Regional Hospital were tested for exposure to tuberculosis after the first patient was diagnosed.  

None of them were sick or showed symptoms.

The province's interim medical officer of health, Dr. Eilish Cleary, said it's expected that "a couple of hundred" people may be tested before the investigation is complete.

Those people would have been in certain units of the regional hospital between Sept. 22 and 25. 

If someone tests positive, he or she will begin taking a combination of antibiotics for up to a year. Cleary said treatment is usually successful if a patient takes the medication as prescribed.

It's not uncommon to see cases of tuberculosis in Nova Scotia, Cleary said, with between two and 10 cases reported every year.