G B Marks1, N V Nhung2, T A Nguyen3, N B Hoa4, T H Khoa5, N V Son5, N T B Phuong6, D M Tin6, J Ho7, G J Fox3. 1. Woolcock Institute of Medical Research, Hanoi, Viet Nam, South Western Sydney Clinical School, University of New South Wales, Sydney, University of Sydney, Sydney, New South Wales, Australia. 2. National Lung Hospital, Hanoi, National TB Control Programme, Hanoi, Viet Nam. 3. Woolcock Institute of Medical Research, Hanoi, Viet Nam, University of Sydney, Sydney, New South Wales, Australia. 4. National Lung Hospital, Hanoi, National TB Control Programme, Hanoi, Viet Nam, Centre for Operational Research, International Union Against Tuberculosis and Lung Disease, Paris, France. 5. National TB Control Programme, Hanoi, Viet Nam, Centre for Social Disease Control, Ca Mau, Viet Nam. 6. Woolcock Institute of Medical Research, Hanoi, Viet Nam. 7. Woolcock Institute of Medical Research, Hanoi, Viet Nam, South Western Sydney Clinical School, University of New South Wales, Sydney.
Abstract
SETTING: The study was conducted in a randomly selected sample of persons aged 15 years living in Ca Mau Province, southern Viet Nam. OBJECTIVE: To estimate the prevalence of latent tuberculous infection (LTBI) in the general adult population of this province of Viet Nam. The secondary objective was to examine age and sex differences in prevalence. DESIGN: A cross-sectional survey was conducted in a cluster-random sample of the population. Clusters were subcommunes. The presence of LTBI was assessed using the QuantiFERON®-TB Gold In-Tube test system. RESULTS: QuantiFERON tests were performed among 1319 persons aged 15 years (77.7% of those selected). The overall prevalence of positive tests was 36.8% (95%CI 33.4-40.3). The prevalence of a positive test was lower in females than in males (31.0% vs. 44.7%, OR 0.57, 95%CI 0.45-0.72, P < 0.0001). The prevalence of positive tests increased with increasing age quintile (P < 0.0001). CONCLUSION: More than one third of the general adult population in a province in southern Viet Nam have evidence of LTBI. Although LTBI prevalence is higher in males, the sex difference is not as great as that for TB notification rates.
SETTING: The study was conducted in a randomly selected sample of persons aged 15 years living in Ca Mau Province, southern Viet Nam. OBJECTIVE: To estimate the prevalence of latent tuberculous infection (LTBI) in the general adult population of this province of Viet Nam. The secondary objective was to examine age and sex differences in prevalence. DESIGN: A cross-sectional survey was conducted in a cluster-random sample of the population. Clusters were subcommunes. The presence of LTBI was assessed using the QuantiFERON®-TB Gold In-Tube test system. RESULTS: QuantiFERON tests were performed among 1319 persons aged 15 years (77.7% of those selected). The overall prevalence of positive tests was 36.8% (95%CI 33.4-40.3). The prevalence of a positive test was lower in females than in males (31.0% vs. 44.7%, OR 0.57, 95%CI 0.45-0.72, P < 0.0001). The prevalence of positive tests increased with increasing age quintile (P < 0.0001). CONCLUSION: More than one third of the general adult population in a province in southern Viet Nam have evidence of LTBI. Although LTBI prevalence is higher in males, the sex difference is not as great as that for TB notification rates.