The Vitalite Health Network said the infected patient was suffering from laryngeal tuberculosis and went to the Dr. Georges-L.-Dumont University Hospital Centre.
Pulmonary test results confirmed last Tuesday that the patient had the highly contagious form of tuberculosis, said Dr. Gabriel Girouard, an infectious disease specialist.
"As soon as the tuberculosis diagnosis was confirmed on Sept. 17, isolation measures were taken," he said.
"We are pleased to see that the patient has been showing clinical sign of improvement since the treatment was started."
Girouard said the risk of infection to others varies and depends on the extent and time of exposure to the infected patient.
No other information about the patient was released by the health authority.
Dr. Yves Leger, the district medical officer of health for the Moncton region, said it might never be known where the patient contracted tuberculosis.
"For a majority of cases they are infected many years or decades ago, and when their immune system becomes low, then at that point the bacteria can reactivate or become active," Leger said.
Leger said New Brunswick usually sees between five and 12 cases of tuberculosis a year, but it issued the public notice in this case because it was a more contagious form of the disease.
About 100 patients who were registered at the hospital's Emergency Department, in the Radiology Department and at its blood test clinic at certain times this month will receive a letter from the hospital, Girouard said.
The health board says affected patients include those who would were at the Emergency Department on Sept. 6 from 10:30 a.m. until 2 p.m., and from Sept. 10 at 11 a.m. until the following day at 10:50 a.m.
Girouard said they also want to hear from anyone else who may have been in those parts of the hospital on those dates.
"We want to collect names of people who have been in the hospital at certain times and eventually go back to the list if we need to test them," he said.
Girouard said the incubation period for tuberculosis is about three weeks, but 90 per cent of the people who are exposed will never develop the disease.