TB control programmes: the challenges for Africa

Governmental neglect of tuberculosis (TB), inadequately managed and inaccurately designed TB control programs, population growth, and the HIV epidemic account for the resurgence of TB in sub-Saharan Africa. The World Health Organization and the International Union against TB and Lung Disease have developed a TB control strategy that aims to reduce mortality, morbidity, and transmission of TB. It aims for an 85% cure rate among detected new cases of smear-positive TB and a 70% rate of detecting existing smear-positive TB cases. The strategy involves the provision of short-course chemotherapy (SCC) to all identified smear-positive TB cases through directly observed treatment (DOTS). SCC treatment regimens for smear-positive pulmonary TB recommended for sub-Saharan African countries are: initial phase = daily administration over 2 months of streptomycin, rifampicin, isoniazid, and pyrazinamide; continuation phase = 3 doses over 4 months of isoniazid and rifampicin or daily administration of thiacetazone and isoniazid or of ethambutol and isoniazid. A TB control policy must be implemented to bring about effective TB control. The essential elements of this policy include political commitment, case detection through passive case-finding, SCC, a regular supply of essential drugs, and a monitoring and evaluation system. Political commitment involves establishing a National TB Control Program to be integrated into the existing health structure. Increased awareness of TB in the community and among health workers and a reference laboratory are needed to make case finding successful. A distribution and logistics system is needed to ensure uninterrupted intake of drugs throughout treatment. These regimens have been very successful and cost-effective but pose several disadvantages (e.g., heavy workload of recommended 3 sputum smear tests). A simplified approach involves 1 initial sputum smear for 6 months; 6-months, intermittent rifampicin-based therapy, 100% DOTS throughout entire treatment course, and ascertainment of treatment completion rates and mortality rates in all patients.     

Tuberculosis situation among tribal population of Car Nicobar, India, 15 years after intensive tuberculosis control project and implementation of a national tuberculosis programme

OBJECTIVE: To assess the tuberculosis (TB) situation in the tribal community of Car Nicobar island 15 years after the national TB programme was implemented in this area after an intensive phase of TB control in 1986. METHODS: The entire population of Car Nicobar was enumerated through a house-to-house survey. Children aged <14 years were tuberculin tested and read for reaction sizes. Individuals aged >15 years were asked about the presence of chest symptoms (cough, chest pain, and unexplained fever for two weeks or longer and haemoptysis), and sputum samples were collected from patients with chest symptoms. Sputum samples were examined for presence of acid-fast bacilli. FINDINGS: Among the 4,543 children enumerated, 4,351 (95.8%) were tuberculin tested and read. Of the 981 children without bacille Calmette-Guerin scars, 161 (16.4%) were infected with TB. A total of 77 cases who were smear-positive for TB were detected from among 10,570 people aged >15 years; the observed smear-positive case prevalence was 728.5 per 100,000. The standardized prevalence of TB infection, annual risk of TB infection, and prevalence of cases smear-positive for TB were 17.0%, 2.5%, and 735.3 per 100,000, respectively. CONCLUSION: The prevalence of TB infection and smear-positive cases of TB increased significantly between 1986 and 2002. Such escalation took place despite the implementation of the national TB programme on this island, which was preceded by a set of special anti-TB measures that resulted in sputum conversion in a substantially large proportion of the smear-positive cases prevalent in the community. The most likely reason for the increase seems to be the absence of a district TB programme with enough efficiency to sustain the gains made from the one-time initial phase of special anti-TB measures. High risk of transmission of TB infection currently observed on this island calls for a drastic and sustained improvement in TB control measures.     

Tuberculosis in Australia: bacteriologically confirmed cases and drug resistance, 2000: report of the Australian Mycobacterium Laboratory Reference Network.

The Australian Mycobacterium Reference Laboratory Network collected and analysed laboratory data on new diagnoses of disease caused by Mycobacterium tuberculosis complex in the year 2000. A total of 765 cases were identified, representing an annual reporting rate of 4.0 cases of laboratory-confirmed tuberculosis (TB) per 100,000 population. Pulmonary disease was diagnosed in 64.9 per cent of cases with a male:female ratio of 1.5:1. Smears were positive for 209/365 (57.3%) of sputum isolates and 39/117 (33.3%) bronchoscopy isolates. Sputum from males was more likely to be smear-positive (63.3%) than from females (47.5%). Isolates from lymph node accounted for 136 (17.7%) of all cases; only 28.7 per cent were smear-positive. Eighty-four (11.0%) isolates, comprising 82 M. tuberculosis and 2 M. bovis strains, demonstrated in vitro resistance to at least one of the standard anti-TB medications. Resistance to at least isoniazid and rifampicin (defined as multidrug-resistant TB) was observed for only 8 (1.0%) strains, a rate similar to previous years. Almost all (96.3%) of patients with drug resistant strains were classified as having initial resistance. The country of birth was known for 76 (92.7%) of 82 patients with a drug resistant strain of M. tuberculosis; 6 were Australian-born and 70 (92.1%) had migrated from a total of 17 countries. Of these 70 migrants with drug-resistant disease, 68.6 per cent had migrated from one of the following countries: Vietnam (n=15), China (n=11), Philippines (n=11), India (n=6), and Indonesia (n=5).     

Tuberculosis: a snap shot picture

In India almost 40% of the population is infected with tuberculosis (TB); 0.4% are sputum-positive infectious cases, 2-2.5 million new cases occur annually, and mortality amounts to 50/100,000 population. The National Tuberculosis Program (NTP) and its District TB Program (DTP) aim to detect all TB cases and treat them effectively as part of the general health services, to vaccinate most children with bacillus Calmette-Guerin, to manage planning and implementation, and to carry out proper recording and reporting of cases. Health education is also carried out in order to enlighten the community, patients, children, students, and medical personnel on various aspects of TB using booklets, pamphlets, TV, and newspaper advertisements. Among resources rendering anti-TB services are 390 district TB centers, 17,850 rural health centers, 330 other clinics, and 17 TB demonstration and training centers; there are approximately 47,000 beds available. International assistance has been obtained from the Swedish International Development Agency, who has supplied X-ray units, anti-TB drugs, and vehicles, since 1979. The World Health Organization (WHO) has assisted by providing consultants, fellowships, and equipment for the National TB Institute in Bangalore and the TB Research Center in Madras. These are also helped by WHO to conduct short courses and training courses for health administrators and college teachers. Some of the problems the NTP faces include: completion of implementation of the DTP in 80 districts and in 25% of peripheral health institutions; nonavailability of trained personnel and vehicles in DTP clinics; overburdened laboratory technicians in 25-30% of primary health care; lack of adequate quantities of drugs, material, and equipment for TB treatment; and lack or shortage of beds. The trends of TB demonstrate that cases tend to concentrate in higher age groups; prevalence in younger people and in newborn children is low and on the decline; and there is a shift from the acute type to the chronic fibrotic type.     

湖南省株洲县1994-2009年结核病控制项目效果分析评价

目的对株洲县1994-2009年实施结核病控制项目效果进行分析评价,为该县结核病控制工作可持续发展提供科学依据。方法对该县1994-2009年登记管理的病人,以病人登记本、月报、季报和年报为资料来源,进行患病率、流行特征、DOTS策略执行情况的分析及社会效益和成本效益的评价研究。结果 1994-2009年登记患病率为72.69/10万,涂阳患病率为45.09/10万,其中新涂阳患病率为36.23/10万,治愈率为93.51%,复治涂阳病人治愈率为88.55%,避免了约60 000人感染结核杆菌和3 000人发生结核病,项目期间产生的直接效益是投入病人发现治疗成本的15倍。结论结核病控制项目的实施,促进了结核病控制规划目标的实现,达到了结核病人高发现率和高治愈率目标,取得了显著的社会效益和经济效益,为结核病控制工作的可持续发展提供了科学依据。     

The missing cases of tuberculosis in Malawi: the contribution from cross-border registrations

Low case detection rates of new smear-positive pulmonary tuberculosis (PTB) patients globally are a cause for concern. The aim of this study was to determine for patients registered for TB in Malawi the number and percentage who lived in a neighbouring country and the registration, recording and reporting practices for these 'foreign' patients. All 44 non-private hospitals, which register and treat all TB patients in the public health sector in Malawi, were visited. Ten (23%) hospitals in 2001 and 14 (32%) in 2002 maintained a separate register for cross-border TB cases. Patients recorded in these registers were not formally reported to the Malawi National TB Programme (NTP), the neighbouring country's NTP, nor to WHO. They therefore constitute missing cases. In Malawi, the number of cross-border new smear-positive PTB cases was 77 in 2001 and 91 in 2002, constituting about 3% of missing smear-positive cases in those hospitals that maintain cross-border registers and about 1% of missing cases nationally.     

Improved Detection of Tuberculosis and Multidrug-Resistant Tuberculosis among Tibetan Refugees,India

The incidence of tuberculosis (TB) among Tibetan refugees in India is 431 cases/100,000 persons, compared with 181 cases/100,000 persons overall in India in 2010. More than half of TB cases in these refugees occur among students, monks, and nuns in congregate settings. We sought to increase TB case detection rates for this population through active case finding and rapid molecular diagnostics. We screened 27,714 persons for symptoms of TB and tested 3,830 symptomatic persons by using an algorithm incorporating chest radiography, sputum smear microscopy, culture, and a rapid diagnostic test; 96 (2.5%) cases of TB were detected (prevalence 346 cases/100,000 persons). Of these cases, 5% were multidrug-resistant TB. Use of the rapid diagnostic test and active case finding enabled rapid detection of undiagnosed TB cases in congregate living settings, which would not have otherwise been identified. The burden of TB in the Tibetan exile population in India is extremely high and requires urgent attention.     

The new tuberculosis

Despite the fact that there are 8 million new cases of tuberculosis (TB) annually and 3 million deaths, TB has been a neglected public health priority, primarily because effective chemotherapy has led to a dramatic decrease in cases in industrialized countries and most cases in developing countries occur in adults. It has only been recently that the emergence of multi-drug resistant TB and the rapid disease progression in HIV-infected persons has led to the application of the methods of modern basic science to TB. Population movement among refugees and immigrants and the neglect of the public health infrastructure have also led to increases in the number of cases worldwide. TB and HIV interact in 4 ways: TB may become reactivated in an HIV-infected person; there may be a primary TB infection, an HIV-positive person may suffer reinfection; or TB may alter the natural history of the HIV infection. In developing countries, the TB seen in association with HIV is believed to be reactivation of latent infection. HIV seropositivity is associated with a 30-50% lifetime risk of TB as compared with a 10% risk in the uninfected. Reactivation of TB in HIV positive people causes an additional 250,000 cases in Africa each year. HIV changes the course of TB; first time exposure is associated with 30-40% attack rates, short incubation periods, and rapid progression of the disease. It is also suggested that TB may hasten the progression of HIV, although this has not been proved. HIV-associated cases of TB will continue to increase in Africa, but in the future the largest number of co-infected persons will be in Asia. The clinical manifestations of HIV-related TB become more severe according to the progression of the immunodeficiency. Patients dying of AIDS who also have TB usually have extremely heavy mycobacterial burdens with widespread, probably incurable, TB. Being HIV-positive is also associated more often with sputum-negative pulmonary or extrapulmonary TB and with atypical radiological manifestations such as absence of cavitation, absence of localization to the upper zones, and the presence of hilar adenopathy, effusions, or infiltrates. Diagnosis may, therefore, be more difficult in cases of HIV infection. Although a greater mortality is found in HIV-positive patients (perhaps associated with complications of other bacterial infections), TB can be treated successfully in HIV-infected people. The World Health Organization recommends short-course chemotherapy of isoniazid, rifampicin, ethambutol, and pyrazinamind for 2 months followed by 4 months of isoiazid and rifampicin or 6 months of isoniazid and ethambutol. The risk of recurrence is greater if non-rifampicin regimens are used and is 3-34 times greater than in seronegative cases. Treatment is complicated by the fact that 18-20% of HIV-positive people have adverse reactions to thiacetazone which presents as a skin condition and can lead to death. Proposed solutions to this problem are to replace thiacetazone with another drug, replace thiacetazone only in HIV-positive persons (testing all patients for HIV), or educating staff and patients about the need to discontinue the drug if a rash occurs. Donor funding will be necessary to adopt a single worldwide approach with the least side effects. Policy decisions must also be made to create a programmatic approach to preventing HIV-associated TB.     

Tuberculosis among health care workers

To assess the annual risk for latent tuberculosis infection (LTBI) among health care workers (HCWs), the incidence rate ratio for tuberculosis (TB) among HCWs worldwide, and the population-attributable fraction of TB to exposure of HCWs in their work settings, we reviewed the literature. Stratified pooled estimates for the LTBI rate for countries with low (<50 cases/100,000 population), intermediate (50-100/100,000 population), and high (>100/100,000 population) TB incidence were 3.8% (95% confidence interval [CI] 3.0%-4.6%), 6.9% (95% CI 3.4%-10.3%), and 8.4% (95% CI 2.7%-14.0%), respectively. For TB, estimated incident rate ratios were 2.4 (95% CI 1.2-3.6), 2.4 (95% CI 1.0-3.8), and 3.7 (95% CI 2.9-4.5), respectively. Median estimated population-attributable fraction for TB was as high as 0.4%. HCWs are at higher than average risk for TB. Sound TB infection control measures should be implemented in all health care facilities with patients suspected of having infectious TB.     

Impact of resistance to anti-tuberculosis drugs on treatment outcome using World Health Organization standard regimens

We compared treatment outcome in 410 patients with drug-susceptible tuberculosis (DS-TB) and 150 patients with drug-resistant tuberculosis (DR-TB) among 560 adult patients (> or = 15 years old) notified with smear-positive pulmonary tuberculosis between July 1997 and June 1998 in the West Province of Cameroon and treated with World Health Organization (WHO) standard regimens under field conditions. Information on treatment outcome was collected for all smear-positive TB patients having a positive culture with drug susceptibility tests performed for isoniazid, rifampicin, ethambutol and streptomycin. Treatment outcome was recorded as cured, completed treatment, failed, defaulted, died or transferred out, 332 of the 410 patients (81%) with DS-TB were cured, compared to 109/150 (72.7%) patients with DR-TB (odds ratio [OR] = 0.62, 95% confidence interval [CI] 0.40-0.99). Seven patients (1.7%) failed treatment in the DS-TB group vs. 9 (6.0%) in the DR-TB group (OR = 3.67, 95% CI 1.23-11.18). No significant difference was found in rates of death, default or transfer. Sputum smear conversion at the end of the intensive treatment phase was observed in 78.8% of the cases, drug resistance having no effect on the conversion rate. After adjusting for age, sex and resistance, the death rate was higher in patients also infected with human immunodeficiency virus (HIV). In TB cases with multidrug resistance, standard regimens result in unacceptably high failure rates (26.1%). For all other drug-resistant forms of TB, rifampicin-based short-course chemotherapy gave satisfactory results. The death toll in the West Province seems due to HIV co-infection rather than to TB alone. To prevent development of drug-resistance, the proportion of defaulters must be decreased and prevention and control strategies endorsed by the WHO and the International Union Against Tuberculosis and Lung Disease must be implemented nation-wide.     

Nosocomial tuberculosis exposure in an outpatient setting: evaluation of patients exposed to healthcare providers with tuberculosis.

OBJECTIVE: To evaluate the risk of tuberculosis (TB) transmission to patients potentially exposed to two healthcare providers who worked in outpatient settings for several weeks prior to being diagnosed with acid-fast bacilli smear-positive pulmonary TB. DESIGN: Potentially exposed patients were notified by letter and television reports of the recommended evaluation for TB infection or disease and availability of free screening at the hospital. Prevalence of infection in the screened patients and the incidence rate of TB over the subsequent 2 years were compared to those of a control group of unexposed outpatients. SETTING: An urban inner-city hospital. PATIENTS: 1,905 patients with potential exposure to the ill healthcare workers; 487 (25%) presented for evaluation. Controls consisted of 951 unexposed patients. RESULTS: 361 potentially exposed patients had their tuberculin test read; 97 (27%) had a purified protein derivative > or = 10 mm. In the comparison group, 148 (25%) of 600 with test readings had a > or = 10-mm reaction (risk ratio, 1.18; 95% confidence interval, 0.86-1.60). In multivariate analysis, male gender, non-white race, and older age were significantly associated with a positive tuberculin test; exposure was not. No TB cases were identified during screening. Two years after the exposure, 7 TB cases had been reported to the state registry among 1,905 potentially exposed patients (184 cases/100,000 person-years) versus 4 cases in the comparison group of 951 (210 cases/100,000 person-years). CONCLUSIONS: Evaluation of patients exposed to healthcare workers with TB disease in ambulatory settings of an inner-city hospital revealed no evidence of transmission of Mycobacterium tuberculosis due to the exposure.     

Epidemiology of Tuberculosis in the Southeastern Iran

In order to study the epidemiology of tuberculosis (TB) in Zabol, situated in the Southeast of Iran, this study was performed. Two thousand seven hundred and twenty-nine cases of tuberculosis disease were identified during 1998–2002. The notification rate was 135/100,000 population in 2002, which was higher than this rate in previous years. The notification rate of TB in Afghan population was significantly higher than Iranian population (202 cases/100,000 in Afghan and 122 cases/100,000 in Iranian population. The case notifications in 1998–2001 were 134, 131, 130, and 130 in 100,000 populations, respectively. The prevalence of smear-positive cases was 76/100,000 population in 2002 and the ratio of smear-positive cases to smear-negative and extrapulmonary cases was 1.46. This region remains high TB rates. It is necessary to pay attention to the detection of TB, by making their register in order to enhance the effectiveness and to reduce the cost of existing methods.     

2003-2007年石家庄市登记新涂阳肺结核病人情况分析

目的了解石家庄市新涂阳肺结核病人特征,以采取更有效的防控措施。方法对2003—2007年石家庄市结核病控制工作季报表资料进行分析。结果2003—2007年石家庄市各级结防机构共登记新涂阳肺结核病人16865例,新涂阳肺结核病人平均登记率为36．61／10万。男性登记数和登记率均高于女性,登记率随年龄增长呈增高的趋势。15—25岁年龄组病人的登记数和占新涂阳总病人数的百分比均最高,15—54岁年龄组的新涂阳病人数占总病人数的66％。23个县、市区平均登记率波动在12．47／10万～44．82／10万。农村县（市）的新涂阳登记率高于石家庄市区,分别为33／10万、12／10万。新涂阳肺结核病人登记率与初诊病人占全人口比例呈正相关（r=0．705）。结论农村最具劳动能力的青壮年为重点发病人群。结核病仍是制约农村地区特别是贫困地区经济和社会发展的重大疾病之一,石家庄市的结核病防控工作的重点仍应放在农村。青年学生也是结核病的高发群体,学校的结核病控制工作应进一步加强。     

2000—2009年上海市金山区活动性肺结核流行病学分析

目的了解上海市金山区肺结核病人发病情况、分布、临床特征及治疗转归情况,为制定结核病防治策略提供依据。方法对2000—2009年金山区活动性肺结核病报告登记管理资料进行分析。结果金山区2000—2009年共新登记该区活动性肺结核病例1 808例,合计发病率为34.42/10万,其中菌阳884例,菌阳率48.89%。金山区共新登记外来流动人口活动性肺结核病例556例,其中菌阳230例,菌阳率41.37%;该区肺结核患者以60岁以上老年人为主,占38.66%,男女性别比为3.26∶1。外来流动人口以青壮年为主,19～40岁占总病例数70.14%,男女性别比为1.79∶1,患者分型以Ⅲ型为主,该区查痰率97.79%,外来流动人口查痰率95.32%。2000—2009年该区涂阳肺结核患者治愈率89.29%,涂阴患者完成疗程率92.73%;2007—2009年外来流动人口涂阳肺结核患者治愈率为67.95%,涂阴患者完成疗程率为81.51%。结论该区活动性肺结核发病率总体趋势略有下降,而菌阳发病率下降趋势不明显;外来流动人口活动性肺结核发病人数呈现上升趋势,菌阳也呈现上升趋势。加强外来流动人口结核病管理,有必要采取切实有效的措施落实外来流动人口的结核病管理。     

No evidence for multiple-drug prophylaxis for tuberculosis compared with isoniazid alone in Southeast Asian refugees and migrants: completion and compliance are major determinants of effectiveness

BACKGROUND: The use of multiple-drug prophylaxis for tuberculosis (TB) has not been shown to be more effective than prophylaxis with isoniazid alone. The boundary between inactive pulmonary TB (class 4 TB) and culture-negative "active" pulmonary TB (class 3 TB) is often unclear, as is the intention to treat such patients as a preventive measure or as a curative measure. METHODS: We compared the effectiveness of single drug preventive therapy with isoniazid to the effectiveness of multiple drug preventive therapy for patients with asymptomatic, inactive TB, in a retrospective cohort study of 984 Southeast (SE) Asian migrants and refugees who received prophylaxis between 1978 and 1980. RESULTS: The rate of TB developing in this cohort was 122 per 100,000 person-years. There was no significant difference in development of TB between people who received isoniazid only and those who received multiple drugs. The only significant predictor of TB was noncompletion of prophylaxis [relative risk (RR) = 62, 95% confidence interval (CI) = 20-194]. Subgroup analysis on people who had completed therapy showed noncompliance as a significant predictor of TB (RR = 16, 95% CI = 1.4-179). The risk of noncompletion (RR = 4.7, 95% CI = 2.37-9.39, P < 0.0001) and noncompliance (RR = 2.2, 95% CI = 1.03-4.7, P = 0.03) was higher for patients who received multiple drugs compared with isoniazid alone. Multiple-drug therapy cost 30 times more than isoniazid alone. CONCLUSIONS: We did not find evidence in support of the empirical practice of giving multiple drugs for prevention of TB. This practice is also more costly and more likely to result in noncompliance and adverse drug reactions.     

Drug resistance profile of Mycobacterium tuberculosis isolates from pulmonary tuberculosis patients in Jos, Nigeria

The drug resistance profile of 100 Mycobacterium tuberculosis isolates from pulmonary tuberculosis (PTB) cases in Jos, Nigeria, was investigated between August 2006 and September 2007. Drug susceptibility testing for 50 new, 11 follow-up and 39 unclassified cases of PTB was performed on L?wenstein-Jensen medium by the proportion method, using isoniazid (0.2 microg/ml), rifampicin (40 microg/ml), ethambutol (2 microg/ml) and streptomycin (4 microg/ml). Susceptibility to all four drugs was found in 76, 62 and 55%, and multidrug resistance (combined resistance to isoniazid and rifampicin with or without resistance to any other drug) in 4, 31 and 18% of the new, unclassified and follow-up cases, respectively. Monoresistance was found in 15% of the cases. Nine of the 16 isolates (56%) showing multidrug resistance were resistant to all four drugs. These findings are critical and the risk to public health is high, particularly with an overall multidrug resistance of 16%. We suggest that TB management and control programs in Jos are revised to enhance patient's accessibility to treatment sites, promote patients' adherence to drugs, improve diagnostic practices, regularly assess drug resistance profiles, and undertake contact tracing for patients with multidrug-resistant TB.     

Antitubercular drug resistance in four healthcare facilities in North India

Tuberculosis (TB) is a major public-health problem in India, having the highest number of incident and multidrug-resistant (MDR) TB cases. The study was carried out to appraise the prevalence of first-line anti-TB drug resistance in Mycobacterium tuberculosis (MTB) and its patterns among different types of TB patients from different settings in a province of North India. Of 3,704 clinical specimens, 345 (9.3%) were culture-positive, and drug-susceptibility testing was carried out for 301 MTB strains. A high level of primary and acquired drug resistance of MTB was observed in the region studied, with weighted mean of 10.5% and 28.08%, 12.81% and 29.72%, 17.12% and 29.94%, 11.97% and 27.84%, and 10.74% and 23.54% for rifampicin, isoniazid, streptomycin, ethambutol-resistant and MDR cases respectively. Drug resistance was significantly higher in pulmonary (p = 0.014) and acquired drug-resistant TB cases (p < 0.001). Any drug resistance (p = 0.002) and MDR TB were significantly (p = 0.009) associated with HIV-seropositive cases. An urgent plan is needed to continuously monitor the transmission trends of drug-resistant strains, especially MDR-TB strains, in the region.     

Prevalence of sputum smear-positive tuberculosis in a rural area in Bangladesh

The objective of the study was to determine the prevalence of smear-positive tuberculosis (TB) in a rural area in Bangladesh at Matlab. A TB surveillance system was established among 106,000 people in rural Bangladesh at Matlab. Trained field workers interviewed all persons aged > or = 15 years to detect suspected cases of TB (cough > 21 days) and sputum specimens of suspected cases were examined for acid-fast bacilli (AFB). Of 59,395 persons interviewed, 4235 (7.1%) had a cough for > 21 days. Sputum specimens were examined for AFB from 3834 persons, 52 (1.4%) of them were positive for AFB. The prevalence of chronic cough and sputum positivity were significantly higher among males compared to females (P < 0.001). The population-based prevalence rate of smear-positive TB cases was 95/100,000 among persons aged > or = 15 years. Cases of TB clustered geographically (relative risk 5.53, 95% CI 3.19-9.59). The high burden of TB among rural population warrants appropriate measures to control TB in Bangladesh. The higher prevalence of persistent cough and AFB-positive sputum among males need further exploration. Factors responsible for higher prevalence of TB in clusters should be investigated.