Incidence of tuberculosis and HIV and progression of silicosis and lung function impairment among former Basotho gold miners.

BACKGROUND: Pulmonary tuberculosis and HIV incidence, mortality, and the progression of silicosis and lung function impairment are described over a 1-year period in migrant ex-gold miners from Lesotho. METHODS: Seven hundred seventy-nine Basotho miners were followed for 1 year starting 18 months after lay-off from a South African gold mine in 1998. At baseline and follow-up, they underwent a respiratory symptom interview, physical examination, HIV test, chest radiograph, and spirometry. RESULTS: Five hundred thirteen of 779 (65.9%) participants attended both baseline and follow-up visits. HIV incidence was 5.4/100 person-years (95% CI: 3.4-8.2). Prevalence of silicosis (ILO score > or =1/1) was 26.6% at baseline and 27.0% at follow-up. Active tuberculosis diagnosed at baseline was a strong predictor of radiological progression of silicosis. Lung function as measured by FEV(1) declined an average of 91 ml between visits (95% CI: 67-116 ml). Calculated minimum incidence of tuberculosis was 3,085/100,000/years (95% CI: 1,797-4,940) at follow-up. Of those seen at baseline, 18 died before their scheduled follow-up visit (mean age: 51 years). CONCLUSIONS: High rates of mortality and of HIV infection and pulmonary tuberculosis were found in this cohort after leaving the South African goldmines. Continuing lung function loss was also apparent. A partnership between the South African mining industry and governments in labor-sending areas of Southern Africa is needed to provide continuity of care and access to HIV and tuberculosis treatment and prevention services. Active silicosis surveillance and an improved statutory compensation system are also needed. These findings can serve as a baseline against which the impact of such interventions can be assessed.

The burden of silicosis, pulmonary tuberculosis and COPD among former Basotho goldminers.

BACKGROUND: The burden of silicosis, pulmonary tuberculosis and COPD is described in 624 South African gold miners 18 months after cessation of work. METHODS: This was a prevalence study. Questionnaires were administered, and spirometry, chest radiography, tuberculosis investigations, and urine HIV antibody assays were performed. RESULTS: Attendance was 80.1% (624/779), mean age 49.4 years, and mean employment duration 25.6 years. Most subjects had had medium (26.5%) or high (65.4%) dust-exposure jobs. Current smoking rate was 35%, with ever smoking 61%. HIV antibodies were detected in the urine in 22.3%. Prevalences were: silicosis 24.6%, past tuberculosis 26%, current tuberculosis 6.2%, airflow obstruction 13.4%, and chronic productive cough 17.7%. Almost 50% of these miners had at least one of these respiratory conditions. CONCLUSIONS: A heavy burden of silicosis, tuberculosis and COPD was present in this group of former goldminers. Intensification of work place dust control measures and TB and HIV prevention activities are needed on South African gold mines. In labor sending communities investment is needed in silicosis and tuberculosis surveillance as well as HIV treatment and care.

High prevalence of tuberculosis in previously treated patients, Cape Town, South Africa.

The tuberculosis (TB) notification rate is high and increasing in 2 communities in Cape Town, South Africa. In 2002, we conducted a prevalence survey among adults > or = 15 years of age to determine the TB prevalence rate; 15% of households in these communities were randomly sampled. All persons living in sampled households were eligible for chest radiography and sputum examination. Of the 3,483 adults who completed a questionnaire, 2,608 underwent chest radiography and sputum examination. We detected 26 bacteriologically confirmed TB cases and a prevalence of 10.0/1,000 (95% confidence interval [CI] 6.2-13.8 per 1,000). We found 18 patients with smear-positive TB, of whom 8 were new patients (3.1/1,000, 95% CI 0.9-5.1/1,000). More than half of patients with smear-positive TB (10, 56%) had previously been treated. Such patients may contribute to transmission of Mycobacterium tuberculosis and the high TB prevalence rate. Successful treatment of TB patients must be a priority.