Survey for tuberculosis in a tribal population in North Arcot District.

SETTING: Tribal villages in the jungles of the Jawadhu hills, South India. OBJECTIVE: To estimate the prevalence of tuberculosis (TB) infection and disease in a remote tribal population. DESIGN: A cross-sectional survey with two-stage screening for identification of cases. A stratified probability proportional sample with the hamlet as the unit. METHODS: Among 56 revenue divisions with a population of about 66,000, 24 revenue divisions were selected. Among 26,320 persons registered, children < 10 years were tuberculin tested and reactions were read after 72 hours. Those over 15 were X-rayed, and tuberculosis symptoms were investigated. Sputum was collected from those with abnormal X-ray or symptoms and examined for smear and culture positivity and sensitivity. RESULTS: Of the 6952 children tested and read, 5% had BCG scars and the prevalence of infection was 5%. The annual risk of infection was 1.1. Among adults, the prevalence of bacillary cases was 8/1000 and X-ray cases 29/1000. The prevalence of bacillary disease was higher among males, particularly with increasing age. Thirty symptomatic cases had normal X-rays and 63 X-ray cases had no symptoms. Thus prevalence would have been underestimated if either method had been used alone for screening. Isoniazid resistance was seen in 12% of patients, two of whom also had rifampicin resistance (2.6%). CONCLUSIONS: The prevalence and pattern of tuberculosis in this tribal group is similar to that observed in non-tribal areas.

Feasibility of involving literate tribal youths in tuberculosis case-finding in a tribal area in Tamil Nadu.

SETTING: Tribal area in South India with a population of 96,000, where the tuberculosis case-finding activity was very poor. OBJECTIVES: To investigate the feasibility of (1) involving literate (who can read and write) tribal youth volunteers for detecting cases of pulmonary tuberculosis (PT) in their respective hamlets; and (2) antituberculosis drug delivery to sputum-positive patients at their homes by village health nurses (VHNs). DESIGN: One volunteer from each of 61 hamlets was selected and trained in the detection of subjects with chest symptoms, sputum collection and transportation to the Primary Health Centre for smear examination. All smear-positive patients were treated with 2RHZ/6TH and the drugs were supplied by VHNs fortnightly at their homes. RESULTS: During a period of 1 year (1992-93), the total population screened was 9383 persons; of these 5755 were aged 15 years and above. A total of 338 symptomatic subjects were identified; 12 sputum-positive cases were detected and started on treatment. Antituberculosis drugs were supplied by VHNs to patients for the first 9 months of the study and by literate youths for the next 3 months. Spot drug checks revealed that 11 of the 12 patients were regular in drug consumption. CONCLUSION: It is feasible to train literate tribal youth volunteers within a short time to detect subjects with chest symptoms in the community and thereby cases of pulmonary tuberculosis. They can serve as an excellent model for community participation in difficult areas.

Critical assessment of smear-positive pulmonary tuberculosis patients after chemotherapy under the district tuberculosis programme.

This is a status report of a retrospectively assembled cohort of 3357 smear-positive patients initiated on anti-tuberculosis chemotherapy in the North Arcot district between April 1986 and March 1988. The patients were contacted once at their homes between November 1988 and June 1989 (6 and 36 months after start of treatment), and information on their status, including death, could be obtained from 76% of them. Regimens were selected by the patients. 2306 (69%) had accepted short course regimens (SCC) and 1051 (31%) had been started on standard chemotherapy (non-SCC), 43% and 35% in SCC and non-SCC respectively had completed 80% or more of their treatment. Overall mortality was 28%. Of those remaining, 31% had active disease and were excreting bacilli, among which 65% of the cultures were resistant to isoniazid and 12% to rifampicin. Combined resistance to isoniazid and rifampicin was seen in 4% and to isoniazid and streptomycin was seen in 19%. A significant finding was that even among those who had taken less than 50% of their treatment, 56% were bacteriologically negative. However, inadequate or irregular chemotherapy resulted in over four times the mortality and about twice the rate of smear positivity as compared with those taking adequate chemotherapy. No comparisons are made between patients on short-course and standard regimens as the patients selected their treatment and the groups are not comparable.