Rapid decline in prevalence of pulmonary tuberculosis after DOTS implementation in a rural area of South India

Tuberculosis Research Centre, Chennai, India.
The International Journal of Tuberculosis and Lung Disease (Impact Factor: 2.32). 08/2008; 12(8):916-20.
Source: PubMed


Tiruvallur District in Tamilnadu, South India, where the World Health Organization-recommended DOTS strategy was implemented as a tuberculosis (TB) control measure in 1999.
To assess the epidemiological impact of the DOTS strategy on the prevalence of pulmonary tuberculosis (PTB).
Surveys of PTB were undertaken on representative population samples aged > or =15 years (n = 83000-90000), before and at 2.5 and 5 years after the implementation of the DOTS strategy. The prevalence of PTB (smear-positive/culture-positive) was estimated.
TB prevalence declined by about 50% in 5 years, from 609 to 311 per 100000 population for culture-positive TB and from 326 to 169/100000 for smear-positive TB. The annual rate of decline was 12.6% (95%CI 11.2-14.0) for culture-positive TB and 12.3% (95%CI 8.6-15.8) for smear-positive TB. The decline was similar at all ages and for both sexes.
With an efficient case detection programme and the DOTS strategy, it is feasible to bring about a substantial reduction in the burden of TB in the community.

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    • "Although the RNTCP was piloted in 1993, it was only implemented in the study district during 2003–04. When effectively implemented over a number of years, the RNTCP has been shown to result in a significant decrease in the prevalence of TB disease, as demonstrated by TRC (NIRT) studies in Thiruvallur district in south India [25]. The performance of RNTCP in Madhya Pradesh state has been gradually improving since it's implementation, with an increase in the case detection rate from 42% in 2001 to 74% in 2010 and in the new smear positive cure rate from 83% in 2001 to 85% in 2009 [26], [27]. "
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    ABSTRACT: The present study provides an estimate of the prevalence of bacteriologially positive pulmonary tuberculosis in Jabalpur, a district in central India. A community based cross-sectional survey was undertaken in Jabalpur District of the central Indian state of Madhya Pradesh. A stratified cluster sampling design was adopted to select the sample. All eligible individuals were questioned for pulmonary symptoms suggestive of TB disease. Two sputum samples were collected from all eligible individuals and were examined by Ziehl-Neelsen smear microscopy and solid media culture methods. Of the 99,918 individuals eligible for screening, 95,071 (95.1%) individuals were screened. Of these, 7,916 (8.3%) were found to have symptoms and sputum was collected from 7,533 (95.2%) individuals. Overall prevalence of bacteriologically positive PTB was found to be 255.3 per 100,000 population (95% C.I: 195.3-315.4). Prevalence was significantly higher (p<0.001) amongst males (355.8; 95% C.I: 304.4-413.4) compared with females (109.0; 95% C.I: 81.2-143.3). Prevalence was also significantly higher in rural areas (348.9; 95% C.I: 292.6-412.8) as compared to the urban (153.9; 95% C.I: 123.2-190.1). The TB situation in Jabalpur district, central India, is observed to be comparable to the TB situation at the national level (255.3 versus 249). There is however, a need to maintain and further strengthen TB control measures on a sustained and long term basis in the area to have a significant impact on the disease prevalence in the community.
    PLoS ONE 08/2012; 7(8):e43225. DOI:10.1371/journal.pone.0043225 · 3.23 Impact Factor
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    • "These large number of undiagnosed TB cases can transmit the disease to others particularly family members. Similar to other studies [8,22,23], we identified more undiagnosed female than male patients. Lack of empowerment to seek early health care and low knowledge of women about the cause of TB [14] could be the reasons for this high number of undiagnosed female TB patients in the community. "
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    BMC Infectious Diseases 03/2012; 12(1):54. DOI:10.1186/1471-2334-12-54 · 2.61 Impact Factor
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    The Indian journal of tuberculosis 02/2009; 56(1):30-43.
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