The changing face of tuberculosis control in a rural district of New Zealand

SETTING: Waikato Health District (WHD), New Zealand. OBJECTIVE: To describe the changing epidemiology of TB in the WHD and the factors responsible for this. DESIGN: Descriptive epidemiological study of all notified TB cases from the WHD from 1 January 1992 to 31 December 2001. Major outcome measures were delay of diagnosis and treatment outcome. RESULTS: There were 244 cases included. Over the 10-year period, TB incidence has remained stable in the WHD. There has been a significant reduction of TB in the Maori population (from 30.3 to 12.5/100 000, P = 0.03). This has been matched by a rise in the overseas-born population (from 4.6 to 21.2/100 000, P = 0.04). Tuberculosis became a predominantly urban disease during the study period. Delay in diagnosis (>4 weeks) occurred in 85% of cases, with significantly more delays in older age groups. Use of directly observed therapy (OR 3.65, 95%CI 1.24-10.76), and being a migrant (OR 3.52, 95%CI 1.74-7.09), were significantly associated with improved treatment outcome. CONCLUSION: A significant change in the epidemiology of TB has occurred over the last decade. Tuberculosis control strategies need to be developed to effectively diagnose and treat patients from diverse cultural backgrounds.