Spoligotype Diversity of Mycobacterium tuberculosis over Two Decades from Tiruvallur, South India.

Geographically, most tuberculosis (TB) cases in 2018 were reported from India. This TB burden is compounded by MDR-TB and XDR-TB. The strategies for the management and control of TB in the community depend on an understanding of the mode of spread of the different strains of TB isolates in the community. To determine the distribution and trends of M. tb strains over the time period in the community due to treatment, we carried out the present study on changes over two decades. Design/Methods. A total of 1218 M. tb isolates (year: 2001-2018) from Tiruvallur, India, were genotyped by spoligotyping after DNA extraction and subjected to anti-TB drug susceptibility testing for the first-line anti-TB drugs. Results. On analysis with the SpolDB4 database, majority (2001-2003: 53.32% and 2015-2018: 46.3%) of the isolates belonged to East African Indian (EAI) lineage, and the orphans designated in comparison to SpolDB4 stood 33% among 2001-2003 strain collection and 46.3% among 2015-2018 strain collection. 10.2% (2001-2003) and 9.26% (2015 to 2018) of isolates were monoresistant to isoniazid (H). MDR strains were less common among EAI strains (3.2%) compared to non-EAI strains (10.32%). Conclusions. EAI is the most predominant lineage in Tiruvallur, despite the presence of highly transmissible lineages like Beijing for the last two decades. The prevalence of MDR-TB is below the national average of 2-3% among the new TB cases in the last two decades. The reason can be attributed to the well-established nature of the locally circulating strains in this region which are not associated with drug resistance.

Trends in the prevalence of pulmonary tuberculosis over a period of seven and half years in a rural community in south India with DOTS.

SETTING: Tiruvallur district In Tamil Nadu where DOTS was implemented by the State Government as the tuberculosis control measure in 1999, and monitored by the National Institute for Research in Tuberculosis for over five years. OBJECTIVE: To estimate trends in TB prevalence in a rural community with DOTS. DESIGN: Surveys of pulmonary tuberculosis were undertaken in representative samples of subjects aged > or =15 years (N = 83,000 - 92,000), initially and after two and half, five and seven and half years of implementation of DOTS. Sputa were collected from those with abnormal radiograph and/or presence of chest symptoms, and examined by direct smear and culture. RESULTS: The prevalence of culture-positive tuberculosis was 607, 454, 309 and 388 per 100,000 in the four surveys, and that of smear-positive tuberculosis was 326, 259, 168 and 180. In the first five years; annual decrease was 12.4% (95% CI 10.4 - 14.4%) for culture-positive tuberculosis, and 12.2% (95% CI 8.0-16.2) for smear-positive tuberculosis. This was, however, followed by a significant increase in the next two and half years. The average new smear-positive case-notification rate was 75 per 100,000 during first four years but declined to 49 in subsequent years. There were no methodological differences during this period and information on changes in socio-economic indicators and nutritional standards was unavailable. CONCLUSION: Despite the average annual success rate (78%) in this tuberculosis unit being lower than the expected rate of 85%, the implementation of DOTS was followed by a substantial decrease in the prevalence of pulmonary tuberculosis over the seven and half year period. Our findings suggest that sustaining the high effectiveness of DOTS programme needs vigilant supervision.

Emergence of drug resistant mutations after single dose nevirapine exposure in HIV-1 infected pregnant women in south India.

BACKGROUND & OBJECTIVES: Resistance to nevirapine (NVP) has been described with single dose preventive regimens in other populations. Our aim was to study the pattern and prevalence of HIV drug resistance (DR) at baseline (during pregnancy) and after delivery among antenatal women exposed to single dose NVP for prevention of parent to child transmission (PPTCT). METHODS: HIV-infected, ART-naive primigravidae between 18-25 years of age, attending government antenatal clinics in Chennai, Vellore or Madurai were recruited. Drug resistance testing was carried out during pregnancy and after Sd-NVP treatment (one month after delivery) by Viroseq sequencing. HIV-1 testing by DNA PCR was done in newborns at 30 days. RESULTS: Thirty one women were enrolled but only twenty six plasma specimens were analyzable (24 paired and two postnatal only). No major mutations were observed in any drug class at baseline though many polymorphisms were observed in both the reverse transcriptase and protease genes. Mutations to non-nucleoside reverse transcriptase inhibitors (NNRTI) were observed post-delivery in 33 per cent of women who were treated with Sd-NVP. None of the infants were HIV-positive. INTERPRETATION & CONCLUSIONS: Among pregnant ART-naive women, baseline HIV drug resistance was not observed. A high rate of development of NNRTI class resistance among women treated with single-dose NVP was observed. Our results emphasize the need to implement more effective PPTCT regimens, minimizing emergence of drug resistance and thereby preserving long-term treatment options for HIV-infected women in India.

Nutritional supplementation in HIV-infected individuals in South India: a prospective interventional study.

BACKGROUND: Malnutrition in human immunodeficiency virus (HIV)-infected individuals is associated with faster disease progression, higher mortality rates, and suboptimal response to antiretroviral therapy (ART). METHODS: We conducted a prospective interventional study to evaluate the effects of an oral macronutrient supplement among HIV-infected adults in South India. Patients attending Tuberculosis Research Centre clinics from June 2005 through December 2007 had baseline nutritional assessment and laboratory investigations performed. Patients at 1 center received nutritional counseling and standard care, whereas patients at 2 centers additionally received a macronutrient providing 400 cal and 15 g of protein daily. Study outcomes were changes in anthropometry, body composition, blood chemistry, and immune status at 6 months. RESULTS: In total, 636 ART-naive patients were enrolled in the study; 361 completed 6 months of follow-up (282 received supplements and 79 received standard care). Mean age +/- standard deviation (SD) was 31 +/- 7 years, mean weight +/- SD was 50 +/- 10 kg, and 42% were male. Significant increases in body weight, body mass index, midarm circumference, fat-free mass, and body cell mass were observed in the supplement group but not in the control group at 6 months; gains were greater in patients with CD4 cell counts <200 cells/microL. No changes were observed in lipid levels, whereas the CD4 cell count decreased in the control group. However, after adjusting for baseline differences, these changes were not statistically significantly different between the groups. CONCLUSIONS: Macronutrient supplementation did not result in significantly increased weight gain compared with standard care (including nutritional counseling) among patients with moderately advanced HIV disease. The effect of supplementation on specific subsets of patients and on preserving immune function needs further research.

First- and second-line drug resistance patterns among previously treated tuberculosis patients in India.

Culture and drug susceptibility testing results of 2816 tuberculosis (TB) patients from across India who had failed repeated treatments from 2001 to 2004 were retrospectively analysed at the Tuberculosis Research Centre, Chennai. Of 1498 (53%) identified as having multidrug-resistant TB (MDR-TB), 671 (44.8%) were resistant to > or =1 second-line drugs (SLDs): 490 (32.7%) to ethionamide, 245 (16.4%) to ofloxacin and 169 (11.3%) to kanamycin; 69 (4.6%) were extensively drug-resistant TB (XDR-TB). Although from a highly select and non-representative patient group, such high SLD resistance levels, including XDR-TB, among MDR-TB patients is of concern. The prevention of MDR/XDR-TB through quality DOTS services, however, remains the priority. In addition, rapid scale-up of quality programmatic management under the RNTCP is needed, with more control and rational use of SLDs outside the programme.

CCR2, MCP-1, SDF-1a & DC-SIGN gene polymorphisms in HIV-1 infected patients with & without tuberculosis.

BACKGROUND & OBJECTIVES: Variability in the clinical outcome of persons exposed to and infected with HIV-1 and tuberculosis (TB) is determined by multiple factors including host genetic variations. The aim of the present study was to find out whether chemokine, chemokine receptor and DC-SIGN gene polymorphisms were associated with susceptibility or resistance to HIV and HIV-TB in south India. METHODS: CCR2 V64I (G/A), monocyte chemoattractant protein-1 (MCP-1) -2518 A/G, stromal cell derived factor-1alpha; (SDF-1alpha) 3'UTR G/A and DC-SIGN gene polymorphisms were studied by polymerase chain reaction based methods in HIV-1 infected patients without TB (n=151), with pulmonary TB (PTB) (n=81) and extrapulmonary TB (n=31), 155 PTB patients without HIV and 206 healthy controls. RESULTS: The genotype frequencies of CCR2 V64I, MCP-1 -2518 and DC-SIGN polymorphisms did not differ significantly between the study groups. A significantly increased frequency of GG genotype of SDF-1alpha polymorphism was observed among HIV+PTB+ patients compared to healthy controls (P=0.009, Pc=0.027). INTERPRETATION & CONCLUSIONS: Our data suggest that GG genotype of SDF-1alpha 3'UTR polymorphism may be associated with susceptibility to PTB in HIV-1 infected patients. A better understanding of genetic factors that are associated with TB could help target preventive strategies to those HIV patients likely to develop tuberculosis.

Surveillance of drug-resistant tuberculosis in the state of Gujarat, India.

BACKGROUND: Limited information about the prevalence of drug-resistant tuberculosis (TB) has been reported from India, the country with the world's highest burden of TB. We conducted a representative state-wide survey in the state of Gujarat (2005 population: 56 million). METHODS: Mycobacterium tuberculosis isolates from a representative sample of new and previously treated smear-positive pulmonary TB (PTB) cases were subjected to drug susceptibility testing (DST) against first-line drugs at a World Health Organization supranational reference laboratory. Isolates found to have at least both isoniazid (INH) and rifampicin (RMP) resistance (i.e., multidrug-resistant TB [MDR-TB]) were subjected to second-line DST. RESULTS: Of 1571 isolates from new patients, 1236 (78.7%) were susceptible to all first-line drugs, 173 (11%) had any INH resistance and MDR-TB was found in 37 (2.4%, 95%CI 1.6-3.1). Of 1047 isolates from previously treated patients, 564 (54%) were susceptible to all first-line drugs, 387 (37%) had any INH resistance and MDR-TB was found in 182 (17.4%, 95%CI 15.0-19.7%). Among 216 MDR-TB isolates, 52 (24%) were ofloxacin (OFX) resistant; seven cases of extensively drug-resistant TB (XDR-TB) were found, all of whom were previously treated cases. CONCLUSION: MDR-TB prevalence remains low among new TB patients in Gujarat, but is more common among previously treated patients. Among MDR-TB isolates, the alarmingly high prevalence of OFX resistance may threaten the success of the expanding efforts to treat and control MDR-TB.

Incomplete immunological recovery following anti-tuberculosis treatment in HIV-infected individuals with active tuberculosis.

BACKGROUND & OBJECTIVE: Mycobacterium tuberculosis infection has been shown to result in increased HIV replication and disease progression in HIV-infected individuals through increased immune activation. The objective of this study was to correlate plasma levels of immune activation markers with the presence of tuberculosis (TB) in HIV-infected and uninfected individuals, and to study the changes following anti-tuberculosis treatment. METHODS: Plasma markers of immune activation - neopterin, beta-2-microglobulin (beta2M) and soluble tumour necrosis factor alpha receptor type I (sTNFalpha-RI) were measured by ELISA in 42 HIV positive TB patients (HIV+TB+) undergoing a six-month course of TB chemotherapy. Thirty seven HIV+ persons without active TB, 38 TB patients without HIV infection, and 62 healthy volunteers served as controls. RESULTS: Plasma levels of all three markers were elevated in HIV+ individuals, more so in those with active TB. When HIV+ individuals were further categorized based on CD4+ T cell counts, HIV+TB+ patients with CD4+ T cells counts

Haplotype analysis of HLA-A, -B antigens and -DRB1 alleles in south Indian HIV-1-infected patients with and without pulmonary tuberculosis.

We have shown earlier the association of human leucocyte antigen (HLA)-A11 with resistance and HLA-B40 and -DR2 with susceptibility to HIV and HIV-TB. In the present study, we have attempted to find out the HLA-DR2 subtypes and the possible HLA-A/-B/-DRB1 haplotype combinations that are associated with susceptibility or resistance to HIV and HIV with pulmonary tuberculosis (HIV+PTB+). HLA-DR2 subtyping was carried out by polymerase chain reaction-based sequence-specific oligonucleotide probe method. Overrepresentation of HLA-DRB1*1501 in HIV-positive PTB-negative (HIV+PTB-) patients (P = 0.004, P(c) = 0.06) and -DRB1*1502 in HIV-positive PTB-positive (HIV+PTB+) patients (P = 0.019) was observed as compared to healthy controls. Haplotype analysis revealed an increased frequency of HLA-A2-DRB1*1501 haplotype in HIV+PTB- patients (P = 0.008) and HLA-A2-DRB1*1502 among HIV+PTB+ patients (P = 0.01) compared to healthy controls. The haplotypes B40-DRB1*1501 and B40-DRB1*04 were found to be moderately increased in HIV+PTB(-) and HIV+PTB+ patients (P < 0.05). The study suggests that HLA-A2-DRB1*1501 haplotype may be associated with HIV infection while HLA-A2-DRB1*1502 haplotype might be associated with susceptibility to PTB in HIV patients. Moreover, HLA-B40-DRB1*1501 and HLA-B40-DRB1*04 haplotypes may be associated with susceptibility to HIV infection and to PTB in HIV patients.

Effect of 1,25 dihydroxyvitamin D3 on intracellular IFN-gamma and TNF-alpha positive T cell subsets in pulmonary tuberculosis.

We studied the immunomodulatory effect of 1,25(OH)(2)D(3) on single cell expression of IFN-gamma and TNF-alpha cytokines in T cell subsets of pulmonary tuberculosis (PTB) patients (n=22) and normal healthy subjects (n=22). Peripheral blood mononuclear cells (PBMCs) were cultured with live Mycobacterium tuberculosis (MTB) with or without 1,25(OH)(2)D(3) (10(-7)M) for 48 h. T cell subsets positive for IFN-gamma and TNF-alpha were enumerated by flow cytometry and the culture supernatants were assayed for both the cytokines using ELISA. In both NHS and PTB patients, a significantly reduced percentage of IFN-gamma and TNF-alpha expressing CD3+, CD3+CD4+ and CD3+CD8+ T cells were observed in cultures stimulated with live MTB and treated with 1,25(OH)(2)D(3) compared to cultures without 1,25(OH)(2)D(3) (NHS; CD3+ IFN-gamma+: p<0.0001; CD3+TNF-alpha+: p=0.0292 and PTB; CD3+ IFN-gamma+: p=0.0292; CD3+ TNF-alpha+: p=0.0028). The levels of IFN-gamma and TNF-alpha in the culture supernatants of 1,25(OH)(2)D(3) treated cultures were also found to be significantly decreased in both groups (NHS; IFN-gamma: p=0.0001; TNF-alpha: p<0.0001) and (PTB; IFN-gamma: p<0.0001; TNF-alpha: p<0.0001). A positive correlation was observed between IFN-gamma and TNF-alpha expressing CD3+CD8+ T cells in MTB stimulated cultures treated with or without 1,25(OH)(2)D(3) in NHS (p=0.0001; p=0.001, respectively) and PTB patients (p=0.002; p=0.005, respectively). The present study revealed the suppressive effect of 1,25(OH)(2)D(3) on single cell expression of IFN-gamma and TNF-alpha by CD3+CD4+ and CD3+CD8+ T cells in pulmonary tuberculosis. This suppressive effect of 1,25(OH)(2)D(3) on proinflammatory and Th1 cytokine positive cells might have a role in reducing inflammation at the site of infection.

Impact of advocacy on the tuberculosis management practices of private practitioners in Chennai City, India.

BACKGROUND: Innovative schemes to ensure the participation of private practitioners (PPs) in the Revised National Tuberculosis Control Programme (RNTCP) are necessary to identify and treat all patients with tuberculosis (TB). We developed a novel public-private mix (PPM) model to encourage PPs to practise DOTS and participate in the RNTCP while retaining their patients. METHODS: The Resource Group for Education and Advocacy for Community Health (REACH) developed and implemented the programme in partnership with the Chennai local health authority and the Tuberculosis Research Centre, Chennai, India. PPs were sensitised to the RNTCP and DOTS through a one-to-one approach or group meetings, and were assisted in referring patients. Surveys were carried out at baseline and at the completion of the study to assess changes in attitudes and practices. RESULTS: Six hundred PPs underwent sensitisation about the RNTCP, after which the proportion of PPs adopting DOTS increased significantly (P < 0.001), and the majority (72.8%) used sputum testing for diagnosing TB. The proportion of PPs who used X-ray alone for diagnosis declined to 16.0% from a baseline of 45.4%. CONCLUSIONS: This PPM model, which emphasises sustained advocacy for DOTS and allows PPs to retain private patients, looks promising and needs to be tested at other sites.

Regulatory role of 1, 25-dihydroxyvitamin D3 and vitamin D receptor gene variants on intracellular granzyme A expression in pulmonary tuberculosis.

Vitamin D receptor (VDR) genotypes have been shown to be associated with differential susceptibility or resistance to tuberculosis. The influence of FokI, BsmI, ApaI and TaqI variants of VDR gene on 1, 25(OH)(2) D(3) modulated granzyme A expression of cytotoxic lymphocytes induced by culture filtrate antigen (CFA) of Mycobacterium tuberculosis was studied in 40 pulmonary tuberculosis (PTB) patients and 49 normal healthy subjects (NHS) by flow cytometry. In both the study groups, addition of 1, 25(OH)(2) D(3) (10(-7)M) significantly reduced the percentage of granzyme A positive cells in both unstimulated (NHS, p<0.0001; PTB, p=0.02) and stimulated culture conditions (CFA, NHS, p<0.0001; PTB, p=0.0001) which correlated positively with the IFN-gamma levels (unstimulated, p=0.01; CFA stimulated, p=0.004) in NHS. The ApaI aa genotype and bbaaTT extended genotype were associated with a significantly decreased percentage of granzyme A positive cells in NHS (p<0.05). Our results suggest that 1, 25(OH)(2) D(3) suppresses granzyme A probably by down-regulating Th1 cytokine response. Moreover, the VDR gene variants might regulate cytotoxic T-cell response via 1, 25(OH)(2) D(3) mediated suppression of granzyme A expression in tuberculosis.

5' regulatory and 3' untranslated region polymorphisms of vitamin D receptor gene in south Indian HIV and HIV-TB patients.

INTRODUCTION: Vitamin D receptor (VDR) gene polymorphisms in the 5' regulatory region (Cdx2 and A-1012G), coding region (FokI), and 3' untranslated region (UTR; BsmI, ApaI, and TaqI) were studied to find out whether these polymorphisms are associated with susceptibility to or protection against HIV-1 and development of tuberculosis (TB) in human immunodeficiency virus (HIV)-1-infected patients. STUDY SUBJECTS AND METHODS: The study was carried out in 131 HIV patients without TB (HIV+ TB-) and 113 HIV patients with TB (HIV+ TB+; includes 82 patients with pulmonary TB (HIV+ PTB+) and 31 with extra pulmonary TB), 108 HIV-negative pulmonary TB patients (HIV- PTB+), and 146 healthy controls. RESULTS: Among the 5' regulatory and coding region polymorphisms, significantly increased frequency of G/A genotype of Cdx-2 was observed in HIV+ TB- group compared to controls (p = 0.012, odds ratio (OR) 1.89 95% confidence interval (CI) 1.14-3.15). In the 3' UTR genotypes, a decreased frequency of b/b genotype of BsmI in total HIV patients (p = 0.014, OR 0.54 95% CI 0.32-0.89) and increased frequencies of A/A genotype of ApaI in HIV+ TB+ patients (p = 0.041, OR 1.77 95% CI 1.02-3.06) and t/t genotype of TaqI in HIV+ PTB+ patients (p = 0.05, OR 2.32 95% CI 0.99-5.46) were observed compared to controls. Haplotype analysis revealed significantly increased frequencies of 3' UTR haplotype B-A-t in HIV+ TB+ and HIV+ PTB+ groups (Pc = 0.030, OR 1.75 95% CI 1.14-2.66) and decreased frequencies of b-A-T haplotype in total HIV patients (Pc = 0.012, OR 0.46 95% CI 0.27-0.77), HIV+ TB- (p = 0.031 OR 0.48 95% CI 0.25-0.89), and HIV+ PTB+ groups (Pc = 0.04, OR 0.47 95% CI 0.23-0.89) compared to controls. CONCLUSIONS: The results suggest that VDR gene 3' UTR haplotype b-A-T may be associated with protection against HIV infection while B-A-t haplotype might be associated with susceptibility to development of TB in HIV-1-infected patients.

DOTS reaches socially marginalized population in the community: a study from a rural area of South India.

We report here that the Directly Observed Treatment, Short course (DOTS) is reaching all tuberculosis patients in the community irrespective of social classification based on the analysis from the tuberculosis prevalence survey and programme performance during 1999-2003 from a rural area in Tamilnadu, South India. New smear- positive cases treated under a DOTS programme were classified in two groups namely; scheduled caste living in colony and other population. The prevalence of smear- positive cases among the scheduled caste population was 1.9 times higher than the other population and this was reflected in the notification also. The successful treatment outcome was also similar in these two groups (75% and 78% respectively; overall 77%). From these findings it is concluded that people living in colony have equal access to DOTS as those in the village.

Assessment of long term status of sputum positive pulmonary TB patients successfully treated with short course chemotherapy.

BACKGROUND: Long term status of pulmonary tuberculosis (PTB) patients treated with short course chemotherapy (SCC) regimens remains unknown. OBJECTIVE: To assess the clinical, bacteriological, radiological status and health related quality of life (HRQoL) of PTB patients 14-18 years after successful treatment with SCC. METHODOLOGY: In a cross-sectional study, cured PTB patients treated during 1986-1990 at the Tuberculosis Research Centre (TRC) were investigated for their current health status including pulmonary function tests (PFT). The St Georges respiratory questionnaire (SGRQ) was used to assess the HRQoL. RESULTS: The mean period after treatment completion for the 363 eligible participants was 16.5 yrs (range 14-18 yrs., 84% coverage); 25 (7%) had been re-treated and 52 (14%) died. Among the investigated, 58 (29%) had persistent respiratory symptoms; 170 (86%) had radiological sequelae but none had active disease. Abnormal PFT was observed in 96 (65%) with predominantly restrictive type of disease in 66 (45%). The SGRQ scores for activity and impact were high implying impairment in HRQoL. CONCLUSION: Assessment of long term status of cured PTB patients showed an impairment of lung functions and HRQoL highlighting the need to address these issues in the management of TB that may provide added value to patient care.

Phenol ammonium sulphate basic fuchsin staining of sputum in pot for the detection of acid-fast bacilli.

BACKGROUND & OBJECTIVES: Improper practices of making direct smears of sputum for detection of acid-fast bacilli (AFB) and of disposing sputum cups are hazardous. The present study was undertaken with the objective to stain sputum samples in their containers by 'phenol (10%) ammonium sulphate (4%) basic fuchsin (2%) solution' and to decolourize and counterstain their smears for detection of AFB- (henceforth called pot method) and to compare the smear results of pot method with the standard Ziehl-Neelsen (ZN) method. METHODS: A total of 575 selected sputum samples from pulmonary tuberculosis patients were stained by the standard ZN and pot methods and the proportions of AFB positive smears were compared. RESULTS: Of the 575 samples, 126 were AFB positive for both the staining methods and the difference was not statistically significant. Pot method missed 9 ZN positive smears (8 scanty and one 1+) and ZN method missed 9 pot positive smears (9 scanty) and the difference was not significant. High grade smears (3+) were seen more in pot method (42) than in ZN method (25) and the difference was significant. INTERPRETATION & CONCLUSION: Our findings showed that pot method was comparable to standard ZN method and had many advantages. Pot method can be explored further for the detection of AFB in sputum samples obtained from pulmonary tuberculosis suspects.

Evaluation of different types of chest symptoms for diagnosing pulmonary tuberculosis cases in community surveys.

BACKGROUND: Prevalence of tuberculosis (TB) is an important epidemiological index to measure the load of the disease in a community. A series of disease surveys were undertaken in rural community in Tiruvallur district in Tamilnadu, south India OBJECTIVE: To investigate the yield of pulmonary tuberculosis (TB) cases by different symptoms status and suggest predominant symptoms for detection of cases in the community based surveys. METHODS: Three disease surveys were conducted during 1999-2006, in a random sample of 82,000 adults aged > or = 15 years to estimate the prevalence and incidence of pulmonary TB. All subjects were screened for chest symptoms and chest radiography. Sputum examination was done among those who were either symptomatic or abnormal on X-ray or both. Cases observed through symptom inquiry were included for analysis. RESULTS: In survey-I, 65.6% had cough of > or = 14 days and yielded 79.1% of the total cases. In surveys II and III, symptomatic subjects with cough contributed 69.5% and 69.2% of the cases respectively. In survey I, 26.8% had symptoms without cough but with at least chest pain > or = 1 month contributed 8.4% of total cases. The corresponding proportions in subsequent surveys were 29.3, 11.5%; and 23.4, 11.2% respectively. The number of symptomatics without cough and chest pain but with fever > or = 1 month was negligible. CONCLUSION: The relative importance of cough as a predominant symptom was reiterated. The yield of pulmonary TB cases from symptomatics having fever of > or = 1 month was negligible. Fever may be excluded from the definition of symptomatics for screening the population in community surveys.