The epidemiology of tuberculosis in Ottawa, Canada, 1995-2004

Abstract

Background: In Ottawa (population 774,072), active tuberculosis (TB) cases are reported to Ottawa Public Health. There has been no comprehensive local epidemiological analysis to date. We report the epidemiology of TB in Ottawa and identify areas of improvement.

Methods: We reviewed TB cases reported to the Reportable Disease Information System from 1995 to 2004 to determine epidemiological characteristics, drug resistance, use of directly observed treatment (DOT) and rates of human immunodeficiency virus (HIV) co-infection.

Results: A total of 584 TB cases (79% foreign-born) were analyzed (average annual incidence 7.5/100,000). Anatomical site of disease followed national trends, with 58% being pulmonary TB. DOT was applied in 49% of total cases. Culture results were available for 385 (66%) and resistance was found in 46 (12%) cases. HIV testing results were available for only 139 cases: 24% were positive.

Conclusion: Overall, Ottawa TB rates are slightly higher than national rates, yet they reflect national trends. The surveillance data were imperfect, with poor or no recording of aboriginal origin, adverse events and treatment outcomes. Reported resistance patterns may be underestimated, as only 66% had cultures. HIV testing was underutilized. Given the high mortality with TB-HIV co-infection, testing should be routine. Correcting these limitations will improve surveillance data and TB control in the future.