Annals of Tropical Medicine and Public Health

: 2016  |  Volume : 9  |  Issue : 4  |  Page : 295--296

Active screening for tuberculosis among slum dwellers in selected urban slums of Puducherry, South India

Palanivel Chinnakali, Pruthu Thekkur, Gomathi Ramaswamy, Kalaiselvi Selvaraj 
 Department of Preventive and Social Medicine, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, Tamil Nadu, India

Correspondence Address:
Palanivel Chinnakali
Department of Preventive and Social Medicine, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, Tamil Nadu

How to cite this article:
Chinnakali P, Thekkur P, Ramaswamy G, Selvaraj K. Active screening for tuberculosis among slum dwellers in selected urban slums of Puducherry, South India.Ann Trop Med Public Health 2016;9:295-296

How to cite this URL:
Chinnakali P, Thekkur P, Ramaswamy G, Selvaraj K. Active screening for tuberculosis among slum dwellers in selected urban slums of Puducherry, South India. Ann Trop Med Public Health [serial online] 2016 [cited 2020 Jul 2 ];9:295-296
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Full Text

Dear Sir,

The World Health Organization's (WHO's) “End TB Strategy” advocates for active case finding activities to have 90% tuberculosis (TB) case detection by 2030.[1] WHO recommends for active screening among household TB contacts, health care workers, people with diabetes, migrants and prisoners, and people in urban slums based on systematic review.[2],[3] The review also recommends for local evidence on active screening in the recommended groups to enable policymakers to develop country specific active screening guidelines.[3],[4] With an estimated 1 million missing TB cases in India, there is a need for determining yield, feasibility, and cost effectiveness of active case finding activities among the recommended high-risk groups.[5] In this study, we aimed to assess the feasibility and yield of active screening among urban slum dwellers.

During the month of March 2013, we conducted a community-based active screening for symptomatic of chest TB in two selected urban slums of Puducherry, Tamil Nadu, India. A house-to-house survey was conducted and informants were interviewed to obtain information on people aged 18 years and above with cough of any duration. In addition, those individuals with cough for duration of more than 2 weeks that produced sputum and if available during the survey were asked to provide a “spot sample” of sputum. One more empty sputum container was provided to them and they were asked to provide early morning sputum, which was eventually collected from their house during a second visit made on the next day. The samples were collected by the informants from those chest TB symptomatics who were not available during the time of visit. Two containers were given to the informants to obtain both “spot” and “early morning” sample. The sputum samples were examined for Acid Fast Bacilli (AFB) in a designated microscopy center (DMC) in a tertiary care hospital. The presence of AFB in any one of the sample was considered as a case of smear positive pulmonary TB. The Revised National Tuberculosis Control Programme guidelines were used to define chest TB symptomatics, obtain sample from chest TB symptomatic, and process the sample in DMC.[6] We calculated number needed to screen (NNS), which is the number of persons that need to undergo screening to diagnose one sputum smear positive TB.

Of 1,178 houses in two urban slums, we enumerated 3,564 adults (1,695 males and 1,851 females) from 1,107 houses. Mean (SD) age of paticipants was 41 (16) years. Of 3,564 participants, 382 (10.8%) reported cough of any duration and 203 (5.7%) reported cough for ≥2 weeks duration. Of 152 participants who had cough for ≥2 weeks with sputum production, 66 (43.4%) provided “spot” sputum sample and 51 (33.5%) provided both “spot” and “early morning” samples. Of 66 participants who provided at least one sputum sample, three individuals were diagnosed as smear positive TB, of which two individuals had a smear grading of 3+. [Figure 1] is a flowchart that provides frequency, proportion, and NNS in each step of the study. Total 280 man hours was spent in active screening, making it 1.5 man hours to identify a chest symptomatic, 94 man hours (4 man days) to detect a case of smear positive TB.{Figure 1}

Of 3,564 participants, past history of TB was reported by 79 (2.2%) individuals and 17 (8.4%) individuals among 203 were chest TB symptomatics. Of 382 with cough of any duration, 224 (58.6%) sought care from any health facilities or chemist shops. Of 203 chest symptomatic, 125 (61.6%) sought any treatment. Half of them (62/125) sought treatment from private healthcare providers, 38% from government facilities, and 12% approached chemist shops.

Findings of this study showed that identifying presumptive TB patients (suspects) is achievable. There was a substantial loss from identification of suspects to sputum examination. In this study, attempts were not made to collect sputum after initial two visits. Experiences from India and other countries have shown that involving community health volunteers (CHV) or community health workers (CHW) will reduce loss of suspects from screening cascade.[7],[8],[9] India being a high TB burden country with a large case detection gap, active case finding among high-risk groups will help in early detection and initiation of TB treatment. There is a need for studies that can provide evidence on effective and efficient diagnostic algorithms that can be adopted to enhance the yield during active screening for TB.

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Conflicts of interest

There are no conflicts of interest.


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