Three decades of tuberculosis in Singapore

Tuberculosis (TB) mortality for the period 1955-1959 to 1985-1989 declined 87% from 72 to 9 per 100,000 in males, and 90% from 31 to 3 per 100,000 in females. The mean annual rate of decline of mortality was 6.8%. Older persons had a lower 4.2-5.2% decline annually compared to 14.1-16.0% in the 0-4 year age group. The incidence of TB declined 80% from 438 to 88 per 100,000 in males, and 71% from 152 to 43 per 100,000 in females over the period 1960-64 to 1985-89. The mean annual rate of decline in incidence was 5.9%. The lowest decline was observed in the children below 15 years (2.8-3.2%) and elderly persons 65 years and above (2.3-5.5%). Birth cohorts of 1945-49 and earlier had progressively higher mortality risks, but declining morbidity risks as they advanced with age. Singapore has overcome the early phase of the TB epidemic as evidenced by its relatively low rates among children and females and the low rates of extra-pulmonary TB and meningitis. The high incidence rates in old people are the residue of even higher rates experienced by this cohort of persons who experienced higher risks of infection in their early lives. At the prevailing rates of decline under the present conditions and control measures, TB will not be eliminated in Singapore over the next 50 years.