Barriers to engagement in the care cascade for tuberculosis disease in India: A systematic review of quantitative studies.

BACKGROUND: India accounts for about one-quarter of people contracting tuberculosis (TB) disease annually and nearly one-third of TB deaths globally. Many Indians do not navigate all care cascade stages to receive TB treatment and achieve recurrence-free survival. Guided by a population/exposure/comparison/outcomes (PECO) framework, we report findings of a systematic review to identify factors contributing to unfavorable outcomes across each care cascade gap for TB disease in India. METHODS AND FINDINGS: We defined care cascade gaps as comprising people with confirmed or presumptive TB who did not: start the TB diagnostic workup (Gap 1), complete the workup (Gap 2), start treatment (Gap 3), achieve treatment success (Gap 4), or achieve TB recurrence-free survival (Gap 5). Three systematic searches of PubMed, Embase, and Web of Science from January 1, 2000 to August 14, 2023 were conducted. We identified articles evaluating factors associated with unfavorable outcomes for each gap (reported as adjusted odds, relative risk, or hazard ratios) and, among people experiencing unfavorable outcomes, reasons for these outcomes (reported as proportions), with specific quality or risk of bias criteria for each gap. Findings were organized into person-, family-, and society-, or health system-related factors, using a social-ecological framework. Factors associated with unfavorable outcomes across multiple cascade stages included: male sex, older age, poverty-related factors, lower symptom severity or duration, undernutrition, alcohol use, smoking, and distrust of (or dissatisfaction with) health services. People previously treated for TB were more likely to seek care and engage in the diagnostic workup (Gaps 1 and 2) but more likely to suffer pretreatment loss to follow-up (Gap 3) and unfavorable treatment outcomes (Gap 4), especially those who were lost to follow-up during their prior treatment. For individual care cascade gaps, multiple studies highlighted lack of TB knowledge and structural barriers (e.g., transportation challenges) as contributing to lack of care-seeking for TB symptoms (Gap 1, 14 studies); lack of access to diagnostics (e.g., X-ray), non-identification of eligible people for testing, and failure of providers to communicate concern for TB as contributing to non-completion of the diagnostic workup (Gap 2, 17 studies); stigma, poor recording of patient contact information by providers, and early death from diagnostic delays as contributing to pretreatment loss to follow-up (Gap 3, 15 studies); and lack of TB knowledge, stigma, depression, and medication adverse effects as contributing to unfavorable treatment outcomes (Gap 4, 86 studies). Medication nonadherence contributed to unfavorable treatment outcomes (Gap 4) and TB recurrence (Gap 5, 14 studies). Limitations include lack of meta-analyses due to the heterogeneity of findings and limited generalizability to some Indian regions, given the country's diverse population. CONCLUSIONS: This systematic review illuminates common patterns of risk that shape outcomes for Indians with TB, while highlighting knowledge gaps-particularly regarding TB care for children or in the private sector-to guide future research. Findings may inform targeting of support services to people with TB who have higher risk of poor outcomes and inform multicomponent interventions to close gaps in the care cascade.

Nutritional supplementation to prevent tuberculosis incidence in household contacts of patients with pulmonary tuberculosis in India (RATIONS): a field-based, open-label, cluster-randomised, controlled trial.

BACKGROUND: In India, tuberculosis and undernutrition are syndemics with a high burden of tuberculosis coexisting with a high burden of undernutrition in patients and in the population. The aim of this study was to determine the effect of nutritional supplementation on tuberculosis incidence in household contacts of adults with microbiologically confirmed pulmonary tuberculosis. METHODS: In this field-based, open-label, cluster-randomised controlled trial, we enrolled household contacts of 2800 patients with microbiologically confirmed pulmonary tuberculosis across 28 tuberculosis units of the National Tuberculosis Elimination Programme in four districts of Jharkhand, India. The tuberculosis units were randomly allocated 1:1 by block randomisation to the control group or the intervention group, by a statistician using computer-generated random numbers. Although microbiologically confirmed pulmonary tuberculosis patients in both groups received food rations (1200 kcal, 52 grams of protein per day with micronutrients) for 6 months, only household contacts in the intervention group received monthly food rations and micronutrients (750 kcal, 23 grams of protein per day with micronutrients). After screening all household contacts for co-prevalent tuberculosis at baseline, all participants were followed up actively until July 31, 2022, for the primary outcome of incident tuberculosis (all forms). The ascertainment of the outcome was by independent medical staff in health services. We used Cox proportional hazards model and Poisson regression via the generalised estimating equation approach to estimate unadjusted hazard ratios, adjusted hazard ratios (aHRs), and incidence rate ratios (IRRs). This study is registered with CTRI-India, CTRI/2019/08/020490. FINDINGS: Between Aug 16, 2019, and Jan 31, 2021, there were 10 345 household contacts, of whom 5328 (94·8%) of 5621 household contacts in the intervention group and 4283 (90·7%) of 4724 household contacts in the control group completed the primary outcome assessment. Almost two-thirds of the population belonged to Indigenous communities (eg, Santhals, Ho, Munda, Oraon, and Bhumij) and 34% (3543 of 10 345) had undernutrition. We detected 31 (0·3%) of 10 345 household contact patients with co-prevalent tuberculosis disease in both groups at baseline and 218 (2·1%) people were diagnosed with incident tuberculosis (all forms) over 21 869 person-years of follow-up, with 122 of 218 incident cases in the control group (2·6% [122 of 4712 contacts at risk], 95% CI 2·2-3·1; incidence rate 1·27 per 100 person-years) and 96 incident cases in the intervention group (1·7% [96 of 5602], 1·4-2·1; 0·78 per 100 person-years), of whom 152 (69·7%) of 218 were patients with microbiologically confirmed pulmonary tuberculosis. Tuberculosis incidence (all forms) in the intervention group had an adjusted IRR of 0·61 (95% CI 0·43-0·85; aHR 0·59 [0·42-0·83]), with an even greater decline in incidence of microbiologically confirmed pulmonary tuberculosis (0·52 [0·35-0·79]; 0·51 [0·34-0·78]). This translates into a relative reduction of tuberculosis incidence of 39% (all forms) to 48% (microbiologically confirmed pulmonary tuberculosis) in the intervention group. An estimated 30 households (111 household contacts) would need to be provided nutritional supplementation to prevent one incident tuberculosis. INTERPRETATION: To our knowledge, this is the first randomised trial looking at the effect of nutritional support on tuberculosis incidence in household contacts, whereby the nutritional intervention was associated with substantial (39-48%) reduction in tuberculosis incidence in the household during 2 years of follow-up. This biosocial intervention can accelerate reduction in tuberculosis incidence in countries or communities with a tuberculosis and undernutrition syndemic. FUNDING: Indian Council of Medical Research-India TB Research Consortium.

Nutritional support for adult patients with microbiologically confirmed pulmonary tuberculosis: outcomes in a programmatic cohort nested within the RATIONS trial in Jharkhand, India.

BACKGROUND: Undernutrition is a common comorbidity of tuberculosis in countries with a high tuberculosis burden, such as India. RATIONS is a field-based, cluster-randomised controlled trial evaluating the effect of providing nutritional support to household contacts of adult patients with microbiologically confirmed pulmonary tuberculosis in Jharkhand, India, on tuberculosis incidence. The patient cohort in both groups of the trial was provided with nutritional support. In this study, we assessed the effects of nutritional support on tuberculosis mortality, treatment success, and other outcomes in the RATIONS patient cohort. METHODS: We enrolled patients (aged 18 years or older) with microbiologically confirmed pulmonary tuberculosis across 28 tuberculosis units. Patients received nutritional support in the form of food rations (1200 kcal and 52 g of protein per day) and micronutrient pills. Nutritional support was for 6 months for drug-susceptible tuberculosis and 12 months for multidrug-resistant tuberculosis; patients with drug-susceptible tuberculosis could receive an extension of up to 6 months if their BMI was less than 18·5 kg/m2 at the end of treatment. We recorded BMI, diabetes status, and modified Eastern Cooperative Oncology Group (ECOG) performance status at baseline. Clinical outcomes (treatment success, tuberculosis mortality, loss to follow-up, and change in performance status) and weight gain were recorded at 6 months. We assessed the predictors of tuberculosis mortality with Poisson and Cox regression using adjusted incidence rate ratios (IRRs) and adjusted hazard ratios (HRs). The RATIONS trial is registered with the Clinical Trials Registry of India (CTRI/2019/08/020490). FINDINGS: Between Aug 16, 2019, and Jan 31, 2021, 2800 patients (mean age 41·5 years [SD 14·5]; 1979 [70·7%] men and 821 [29·3%] women) were enrolled. At enrolment, 2291 (82·4%) patients were underweight (BMI <18·5 kg/m2), and 480 (17·3%) had a BMI of less than 14 kg/m2. The mean weight and BMI were 42·6 kg (SD 7·8) and 16·4 kg/m2 (2·6) in men and 36·1 kg (7·3) and 16·2 kg/m2 (2·9) in women. During the 6-month follow-up, treatment was successful in 2623 (93·7%) patients, 108 (3·9%) tuberculosis deaths occurred, 28 (1·0%) patients were lost to follow-up, and treatment failure was experienced by five (0·2%) patients. The median weight gain was 4·6 kg (IQR 2·8-6·8), but 1441 (54·8%) of 2630 patients remained underweight. At 2 months, 1444 (54·0%) of 2676 patients gained at least 5% of baseline weight. Baseline weight (adjusted IRR 0·95, 95% CI 0·90-0·99), BMI (0·88, 0·76-1·01), poor performance status (ECOG categories 3-4; 5·33, 2·90-9·79), diabetes (3·30, 1·65-6·72), and haemoglobin (0·85, 0·71-1·00) were predictors of tuberculosis mortality. A reduced hazard of death (adjusted HR 0·39, 95% CI 0·18-0·86) was associated with a 5% weight gain at 2 months. INTERPRETATION: In this study, nutritional support was provided to a cohort with a high prevalence of severe undernutrition. Weight gain, particularly in the first 2 months, was associated with a substantially decreased hazard of tuberculosis mortality. Nutritional support needs to be an integral component of patient-centred care to improve treatment outcomes in such settings. FUNDING: India Tuberculosis Research Consortium, Indian Council of Medical Research.

In-vitro anti-Mycobacterium tuberculosis effect of Eugenol.

BACKGROUND/OBJECTIVES: Mycobacterium tuberculosis, the causative agent of tuberculosis has developed resistance to most of the available antimicrobials. Therefore research on the detection of new antimicrobials against Mycobacterium tuberculosis is needed urgently. Essential oils extracted from plants have been shown to have anti-Mycobacterium tuberculosis effect in in-vitro experiments. Essential oil contains many chemicals and any one or more than one chemical may have the anti-Mycobacterium tuberculosis effect. Eugenol is one such chemical in the essential oil and the anti-Mycobacterium tuberculosis effect of eugenol is investigated. METHODS: The anti-Mycobacterium tuberculosis effect of eugenol was evaluated against H37Rv and twelve clinical isolates of Mycobacterium tuberculosis in the BD BACTEC MGIT instrument using different volumes of eugenol. RESULTS: H37Rv and all the twelve clinical isolates of Mycobacterium tuberculosis were inhibited by eugenol. The minimal inhibitory concentration of H37Rv was 2.5 µl (2.67 mg) and those of the clinical isolates of Mycobacterium tuberculosis ranged from to 2.5 µl (2.67 mg) to 10 µl (10.68 mg). CONCLUSION: Eugenol has anti-Mycobacterium tuberculosis effect in the in-vitro BD BACTEC MGIT method.

Predictors of mortality among hospitalized COVID-19 patients and risk score formulation for prioritizing tertiary care-An experience from South India.

BACKGROUND: We retrospectively data-mined the case records of Reverse Transcription Polymerase Chain Reaction (RT-PCR) confirmed COVID-19 patients hospitalized to a tertiary care centre to derive mortality predictors and formulate a risk score, for prioritizing admission. METHODS AND FINDINGS: Data on clinical manifestations, comorbidities, vital signs, and basic lab investigations collected as part of routine medical management at admission to a COVID-19 tertiary care centre in Chengalpattu, South India between May and November 2020 were retrospectively analysed to ascertain predictors of mortality in the univariate analysis using their relative difference in distribution among 'survivors' and 'non-survivors'. The regression coefficients of those factors remaining significant in the multivariable logistic regression were utilised for risk score formulation and validated in 1000 bootstrap datasets. Among 746 COVID-19 patients hospitalised [487 "survivors" and 259 "non-survivors" (deaths)], there was a slight male predilection [62.5%, (466/746)], with a higher mortality rate observed among 40-70 years age group [59.1%, (441/746)] and highest among diabetic patients with elevated urea levels [65.4% (68/104)]. The adjusted odds ratios of factors [OR (95% CI)] significant in the multivariable logistic regression were SaO2<95%; 2.96 (1.71-5.18), Urea ≥50 mg/dl: 4.51 (2.59-7.97), Neutrophil-lymphocytic ratio (NLR) >3; 3.01 (1.61-5.83), Age ≥50 years;2.52 (1.45-4.43), Pulse Rate ≥100/min: 2.02 (1.19-3.47) and coexisting Diabetes Mellitus; 1.73 (1.02-2.95) with hypertension and gender not retaining their significance. The individual risk scores for SaO2<95-11, Urea ≥50 mg/dl-15, NLR >3-11, Age ≥50 years-9, Pulse Rate ≥100/min-7 and coexisting diabetes mellitus-6, acronymed collectively as 'OUR-ARDs score' showed that the sum of scores ≥ 25 predicted mortality with a sensitivity-90%, specificity-64% and AUC of 0.85. CONCLUSIONS: The 'OUR ARDs' risk score, derived from easily assessable factors predicting mortality, offered a tangible solution for prioritizing admission to COVID-19 tertiary care centre, that enhanced patient care but without unduly straining the health system.

In-vitro anti-Mycobacterium tuberculosis effect of essential oil of Ocimum sanctum L. (Tulsi/Basil) leaves.

BACKGROUND/OBJECTIVES: Mycobacterium tuberculosis, the causative agent of tuberculosis has developed resistance to most of the available antimicrobials. Consequently, it is difficult to cure all the patients with tuberculosis and in future, the incidence of tuberculosis by drug resistant M. tuberculosis is likely to increase, worldwide. Therefore detection and development of new antimicrobials against M. tuberculosis is needed urgently. METHODS: Essential oil from the leaves of Ocimum sanctum L (Tulsi/Basil) was obtained by hydro distillation. The anti-mycobacterial effect of essential oil was evaluated against H37Rv and nine clinical isolates of M. tuberculosis in the BD BACTEC MGIT instrument using different volumes of essential oil. RESULTS: The essential oil inhibited the growth of H37Rv and all the nine clinical isolates of M. tuberculosis. The minimal inhibitory concentration of H37Rv was 3 µl (2.931 µg) and those of the clinical isolates of M. tuberculosis ranged from 1.5 µl (1.4655 µg) to 6 µl (5.862 µg). CONCLUSION: The Essential oil from the leaves of O. sanctum L.(Tulsi/Basil) has anti-M. tuberculosis effect in the in-vitro BD BACTEC MGIT method.

Prevalence of pulmonary tuberculosis among the tribal populations in India.

IMPORTANCE: There is no concrete evidence on the burden of TB among the tribal populations across India except for few studies mainly conducted in Central India with a pooled estimation of 703/100,000 with a high degree of heterogeneity. OBJECTIVE: To estimate the prevalence of TB among the tribal populations in India. DESIGN, PARTICIPANTS, SETTING: A survey using a multistage cluster sampling design was conducted between April 2015 and March 2020 covering 88 villages (clusters) from districts with over 70% tribal majority populations in 17 States across 6 zones of India. The sample populations included individuals ≥15 years old. MAIN OUTCOME AND MEASURES: Eligible participants who were screened through an interview for symptoms suggestive of pulmonary TB (PTB); Two sputum specimens were examined by smear and culture. Prevalence was estimated after multiple imputations for non-coverage and a correction factor of 1.31 was then applied to account for non-inclusion of X-ray screening. RESULTS: A total of 74532 (81.0%) of the 92038 eligible individuals were screened; 2675 (3.6%) were found to have TB symptoms or h/o ATT. The overall prevalence of PTB was 432 per 100,000 populations. The PTB prevalence per 100,000 populations was highest 625 [95% CI: 496-754] in the central zone and least 153 [95% CI: 24-281] in the west zone. Among the 17 states that were covered in this study, Odisha recorded the highest prevalence of 803 [95% CI: 504-1101] and Jammu and Kashmir the lowest 127 [95% CI: 0-310] per 100,000 populations. Findings from multiple logistic regression analysis reflected that those aged 35 years and above, with BMI <18.5 Kgs /m2, h/o ATT, smoking, and/or consuming alcohol had a higher risk of bacteriologically positive PTB. Weight loss was relatively more important symptom associated with tuberculosis among this tribal populations followed by night sweats, blood in sputum, and fever. CONCLUSION AND RELEVANCE: The overall prevalence of PTB among tribal groups is higher than the general populations with a wide variation of prevalence of PTB among the tribal groups at zone and state levels. These findings call for strengthening of the TB control efforts in tribal areas to reduce TB prevalence through tribal community/site-specific intervention programs.

Training strategies practiced for TB elimination.

Training is the backbone of any public health program and it is true for a vast program like TB. It is urgent when the program is aiming to End TB. The strategy that is followed in India for capacity building of TB workers is presented in this article. Various types of trainings that are needed are described in detail. Also enlisted are the different trainings undertaken at NTI for the last five years. Recent times the effect of Covid-19 has resulted in the acceleration of the effort of going for digital platforms and onlinetrainings and is described.

Pretreatment Out-of-Pocket Expenses for Presumptive Multidrug-Resistant Tuberculosis Patients, India, 2016-2017.

In India, under the National Tuberculosis Elimination Programme, the government provides free treatment for multidrug-resistant tuberculosis; however, many patients seek care elsewhere, which is costly. To determine those out-of-pocket expenses, we interviewed 40 presumptive patients and found that they spent more than their median annual income before registering for the government program.

Constructing care cascades for active tuberculosis: A strategy for program monitoring and identifying gaps in quality of care.

The cascade of care is a model for evaluating patient retention across sequential stages of care required to achieve a successful treatment outcome. This approach was first used to evaluate HIV care and has since been applied to other diseases. The tuberculosis (TB) community has only recently started using care cascade analyses to quantify gaps in quality of care. In this article, we describe methods for estimating gaps (patient losses) and steps (patients retained) in the care cascade for active TB disease. We highlight approaches for overcoming challenges in constructing the TB care cascade, which include difficulties in estimating the population-level burden of disease and the diagnostic gap due to the limited sensitivity of TB diagnostic tests. We also describe potential uses of this model for evaluating the impact of interventions to improve case finding, diagnosis, linkage to care, retention in care, and post-treatment monitoring of TB patients.

Developing a model to predict unfavourable treatment outcomes in patients with tuberculosis and human immunodeficiency virus co-infection in Delhi, India.

BACKGROUND: Tuberculosis (TB) patients with human immunodeficiency virus (HIV) co-infection have worse TB treatment outcomes compared to patients with TB alone. The distribution of unfavourable treatment outcomes differs by socio-demographic and clinical characteristics, allowing for early identification of patients at risk. OBJECTIVE: To develop a statistical model that can provide individual probabilities of unfavourable outcomes based on demographic and clinical characteristics of TB-HIV co-infected patients. METHODOLOGY: We used data from all TB patients with known HIV-positive test results (aged ≥15 years) registered for first-line anti-TB treatment (ATT) in 2015 under the Revised National TB Control Programme (RNTCP) in Delhi, India. We included variables on demographics and pre-treatment clinical characteristics routinely recorded and reported to RNTCP and the National AIDS Control Organization. Binomial logistic regression was used to develop a statistical model to estimate probabilities of unfavourable TB treatment outcomes (i.e., death, loss to follow-up, treatment failure, transfer out of program, and a switch to drug-resistant regimen). RESULTS: Of 55,260 TB patients registered for ATT in 2015 in Delhi, 928 (2%) had known HIV-positive test results. Of these, 816 (88%) had drug-sensitive TB and were ≥15 years. Among 816 TB-HIV patients included, 157 (19%) had unfavourable TB treatment outcomes. We developed a model for predicting unfavourable outcomes using age, sex, disease classification (pulmonary versus extra-pulmonary), TB treatment category (new or previously treated case), sputum smear grade, known HIV status at TB diagnosis, antiretroviral treatment at TB diagnosis, and CD4 cell count at ATT initiation. The chi-square p-value for model calibration assessed using the Hosmer-Lemeshow test was 0.15. The model discrimination, measured as the area under the receiver operator characteristic (ROC) curve, was 0.78. CONCLUSION: The model had good internal validity, but should be validated with an independent cohort of TB-HIV co-infected patients to assess its performance before clinical or programmatic use.

Tuberculosis preventive treatment: the next chapter of tuberculosis elimination in India.

The End TB Strategy envisions a world free of tuberculosis-zero deaths, disease and suffering due to tuberculosis by 2035. This requires reducing the global tuberculosis incidence from >1250 cases per million people to <100 cases per million people within the next two decades. Expanding testing and treatment of tuberculosis infection is critical to achieving this goal. In high-burden countries, like India, the implementation of tuberculosis preventive treatment (TPT) remains a low priority. In this analysis article, we explore potential challenges and solutions of implementing TPT in India. The next chapter in tuberculosis elimination in India will require cost-effective and sustainable interventions aimed at tuberculosis infection. This will require constant innovation, locally driven solutions to address the diverse and dynamic tuberculosis epidemiology and persistent programme monitoring and evaluation. As new tools, regimens and approaches emerge, midcourse adjustments to policy and practice must be adopted. The development and implementation of new tools and strategies will call for close collaboration between local, national and international partners-both public and private-national health authorities, non-governmental organisations, research community and the diagnostic and pharmaceutical industry. Leading by example, India can contribute to global knowledge through operational research and programmatic implementation for combating tuberculosis infection.

Recurrence of tuberculosis among newly diagnosed sputum positive pulmonary tuberculosis patients treated under the Revised National Tuberculosis Control Programme, India: A multi-centric prospective study.

INTRODUCTION: There is lack of information on the proportion of new smear-positive pulmonary tuberculosis (PTB) patients treated with a 6-month thrice-weekly regimen under Revised National Tuberculosis Control Programme (RNTCP) who develop recurrent TB after successful treatment outcome. OBJECTIVE: To estimate TB recurrence among newly diagnosed PTB patients who have successfully completed treatment and to document endogenous reactivation or re-infection. Risk factors for unfavourable outcomes to treatment and TB recurrence were determined. METHODOLOGY: Adult (aged ≥ 18 yrs) new smear positive PTB patients initiated on treatment under RNTCP were enrolled from sites in Tamil Nadu, Karnataka, Delhi, Maharashtra, Madhya Pradesh and Kerala. Those declared "treatment success" at the end of treatment were followed up with 2 sputum examinations each at 3, 6 and 12 months after treatment completion. MIRU-VNTR genotyping was done to identify endogenous re-activation or exogenous re-infection at TB recurrence. TB recurrence was expressed as rate per 100 person-years (with 95% confidence interval [95%CI]). Regression models were used to identify the risk factors for unfavourable response to treatment and TB recurrence. RESULTS: Of the1577 new smear positive PTB patients enrolled, 1565 were analysed. The overall cure rate was 77% (1207/1565) and treatment success was 77% (1210 /1565). The cure rate varied from 65% to 86%. There were 158 of 1210 patients who had TB recurrence after treatment success. The pooled TB recurrence estimate was 10.9% [95%CI: 0.2-21.6] and TB recurrence rate per 100 person-years was 12.7 [95% CI: 0.4-25]. TB recurrence per 100 person-years varied from 5.4 to 30.5. Endogenous reactivation was observed in 56 (93%) of 60 patients for whom genotyping was done. Male gender was associated with TB recurrence. CONCLUSION: A substantial proportion of new smear positive PTB patients successfully treated with 6 -month thrice-weekly regimen have TB recurrence under program settings.

Operational research within a Global Fund supported tuberculosis project in India: why, how and its contribution towards change in policy and practice.

BACKGROUND: The Global Fund encourages operational research (OR) in all its grants; however very few reports describe this aspect. In India, Project Axshya was supported by a Global Fund grant to improve the reach and visibility of the government Tuberculosis (TB) services among marginalised and vulnerable communities. OR was incorporated to build research capacity of professionals working with the national TB programme and to generate evidence to inform policies and practices. OBJECTIVES: To describe how Project Axshya facilitated building OR capacity within the country, helped in addressing several TB control priority research questions, documented project activities and their outcomes, and influenced policy and practice. METHODS: From September 2010 to September 2016, three key OR-related activities were implemented. First, practical output-oriented modular training courses were conducted (n = 3) to build research capacity of personnel involved in the TB programme, co-facilitated by The Union, in collaboration with the national TB programme, WHO country office and CDC, Atlanta. Second, two large-scale Knowledge, Attitude and Practice (KAP) surveys were conducted at baseline and mid-project to assess the changes pertaining to TB knowledge, attitudes and practices among the general population, TB patients and health care providers over the project period. Third, studies were conducted to describe the project's core activities and outcomes. RESULTS: In the training courses, 44 participant teams were supported to develop research protocols on topics of national priority, resulting in 28 peer-reviewed scientific publications. The KAP surveys and description of project activities resulted in 14 peer-reviewed publications. Of the published papers at least 12 have influenced change in policy or practice. CONCLUSIONS: OR within a Global Fund supported TB project has resulted in building OR capacity, facilitating research in areas of national priority and influencing policy and practice. We believe this experience will provide guidance for undertaking OR in Global Fund projects.

Prevalence of pulmonary tuberculosis among adults in selected slums of Delhi city.

BACKGROUND: A survey was carried out to estimate the point prevalence of bacteriologically positive pulmonary tuberculosis (PTB) among persons ≥15 years of age residing in Jhuggi-Jhopri (JJ) colonies - urban slums in Delhi, India implementing Directly Observed Treatment strategy since 1998. METHODS: Among 12 JJ colonies selected by simple random sampling, persons having persistent cough for ≥2 weeks at the time of the survey or cough of any duration along with history of contact/currently on ant-TB treatment/known HIV positive were subjected to sputum examination - 2 specimens, by smear microscopy for Acid Fast Bacilli and culture for Mycobacterium tuberculosis. Persons with at least one specimen positive were labelled as bacteriologically confirmed PTB. Prevalence was estimated after imputing missing values to correct bias introduced by incompleteness of data and corrected for non-screening by X-ray by a multiplication factor derived from recently conducted surveys. RESULTS: Of 40,756 persons registered, 40,529 (99.4%) were screened. Of them, 691 (2%) were eligible for sputum examination. Spot specimens were collected from 659 (99.2%) and early morning sputum specimens from 647 (98.1%). Using screening by interview alone, prevalence of bacteriologically positive PTB in persons ≥15 years of age was estimated at 160.4 (123.7-197.1) per 100,000 populations and210.0 (CI: 162.5-258.2) after correcting for non-screening by X-ray. CONCLUSION: Observed prevalence suggests further strengthening of TB control program in urban slums.

Counting the lives saved by DOTS in India: a model-based approach.

BACKGROUND: Against the backdrop of renewed efforts to control tuberculosis (TB) worldwide, there is a need for improved methods to estimate the public health impact of TB programmes. Such methods should not only address the improved outcomes amongst those receiving care but should also account for the impact of TB services on reducing transmission. METHODS: Vital registration data in India are not sufficiently reliable for estimates of TB mortality. As an alternative approach, we developed a mathematical model of TB transmission dynamics and mortality, capturing the scale-up of DOTS in India, through the rollout of the Revised National TB Control Programme (RNTCP). We used available data from the literature to calculate TB mortality hazards amongst untreated TB; amongst cases treated under RNTCP; and amongst cases treated under non-RNTCP conditions. Using a Bayesian evidence synthesis framework, we combined these data with current estimates for the TB burden in India to calibrate the transmission model. We simulated the national TB epidemic in the presence and absence of the DOTS programme, measuring lives saved as the difference in TB deaths between these scenarios. RESULTS: From 1997 to 2016, India's RNTCP has saved 7.75 million lives (95% Bayesian credible interval 6.29-8.82 million). We estimate that 42% of this impact was due to the 'indirect' effects of the RNTCP in averting transmission as well as improving treatment outcomes. CONCLUSIONS: When expanding high-quality TB services, a substantial proportion of overall impact derives from preventive, as well as curative, benefits. Mathematical models, together with sufficient data, can be a helpful tool in estimating the true population impact of major disease control programmes.

Feasibility of achieving the 2025 WHO global tuberculosis targets in South Africa, China, and India: a combined analysis of 11 mathematical models.

BACKGROUND: The post-2015 End TB Strategy proposes targets of 50% reduction in tuberculosis incidence and 75% reduction in mortality from tuberculosis by 2025. We aimed to assess whether these targets are feasible in three high-burden countries with contrasting epidemiology and previous programmatic achievements. METHODS: 11 independently developed mathematical models of tuberculosis transmission projected the epidemiological impact of currently available tuberculosis interventions for prevention, diagnosis, and treatment in China, India, and South Africa. Models were calibrated with data on tuberculosis incidence and mortality in 2012. Representatives from national tuberculosis programmes and the advocacy community provided distinct country-specific intervention scenarios, which included screening for symptoms, active case finding, and preventive therapy. FINDINGS: Aggressive scale-up of any single intervention scenario could not achieve the post-2015 End TB Strategy targets in any country. However, the models projected that, in the South Africa national tuberculosis programme scenario, a combination of continuous isoniazid preventive therapy for individuals on antiretroviral therapy, expanded facility-based screening for symptoms of tuberculosis at health centres, and improved tuberculosis care could achieve a 55% reduction in incidence (range 31-62%) and a 72% reduction in mortality (range 64-82%) compared with 2015 levels. For India, and particularly for China, full scale-up of all interventions in tuberculosis-programme performance fell short of the 2025 targets, despite preventing a cumulative 3·4 million cases. The advocacy scenarios illustrated the high impact of detecting and treating latent tuberculosis. INTERPRETATION: Major reductions in tuberculosis burden seem possible with current interventions. However, additional interventions, adapted to country-specific tuberculosis epidemiology and health systems, are needed to reach the post-2015 End TB Strategy targets at country level. FUNDING: Bill and Melinda Gates Foundation.

Cost-effectiveness and resource implications of aggressive action on tuberculosis in China, India, and South Africa: a combined analysis of nine models.

BACKGROUND: The post-2015 End TB Strategy sets global targets of reducing tuberculosis incidence by 50% and mortality by 75% by 2025. We aimed to assess resource requirements and cost-effectiveness of strategies to achieve these targets in China, India, and South Africa. METHODS: We examined intervention scenarios developed in consultation with country stakeholders, which scaled up existing interventions to high but feasible coverage by 2025. Nine independent modelling groups collaborated to estimate policy outcomes, and we estimated the cost of each scenario by synthesising service use estimates, empirical cost data, and expert opinion on implementation strategies. We estimated health effects (ie, disability-adjusted life-years averted) and resource implications for 2016-35, including patient-incurred costs. To assess resource requirements and cost-effectiveness, we compared scenarios with a base case representing continued current practice. FINDINGS: Incremental tuberculosis service costs differed by scenario and country, and in some cases they more than doubled existing funding needs. In general, expansion of tuberculosis services substantially reduced patient-incurred costs and, in India and China, produced net cost savings for most interventions under a societal perspective. In all three countries, expansion of access to care produced substantial health gains. Compared with current practice and conventional cost-effectiveness thresholds, most intervention approaches seemed highly cost-effective. INTERPRETATION: Expansion of tuberculosis services seems cost-effective for high-burden countries and could generate substantial health and economic benefits for patients, although substantial new funding would be required. Further work to determine the optimal intervention mix for each country is necessary. FUNDING: Bill & Melinda Gates Foundation.

The Tuberculosis Cascade of Care in India's Public Sector: A Systematic Review and Meta-analysis.

BACKGROUND: India has 23% of the global burden of active tuberculosis (TB) patients and 27% of the world's "missing" patients, which includes those who may not have received effective TB care and could potentially spread TB to others. The "cascade of care" is a useful model for visualizing deficiencies in case detection and retention in care, in order to prioritize interventions. METHODS AND FINDINGS: The care cascade constructed in this paper focuses on the Revised National TB Control Programme (RNTCP), which treats about half of India's TB patients. We define the TB cascade as including the following patient populations: total prevalent active TB patients in India, TB patients who reach and undergo evaluation at RNTCP diagnostic facilities, patients successfully diagnosed with TB, patients who start treatment, patients retained to treatment completion, and patients who achieve 1-y recurrence-free survival. We estimate each step of the cascade for 2013 using data from two World Health Organization (WHO) reports (2014-2015), one WHO dataset (2015), and three RNTCP reports (2014-2016). In addition, we conduct three targeted systematic reviews of the scientific literature to identify 39 unique articles published from 2000-2015 that provide additional data on five indicators that help estimate different steps of the TB cascade. We construct separate care cascades for the overall population of patients with active TB and for patients with specific forms of TB-including new smear-positive, new smear-negative, retreatment smear-positive, and multidrug-resistant (MDR) TB. The WHO estimated that there were 2,700,000 (95%CI: 1,800,000-3,800,000) prevalent TB patients in India in 2013. Of these patients, we estimate that 1,938,027 (72%) TB patients were evaluated at RNTCP facilities; 1,629,906 (60%) were successfully diagnosed; 1,417,838 (53%) got registered for treatment; 1,221,764 (45%) completed treatment; and 1,049,237 (95%CI: 1,008,775-1,083,243), or 39%, of 2,700,000 TB patients achieved the optimal outcome of 1-y recurrence-free survival. The separate cascades for different forms of TB highlight different patterns of patient attrition. Pretreatment loss to follow-up of diagnosed patients and post-treatment TB recurrence were major points of attrition in the new smear-positive TB cascade. In the new smear-negative and MDR TB cascades, a substantial proportion of patients who were evaluated at RNTCP diagnostic facilities were not successfully diagnosed. Retreatment smear-positive and MDR TB patients had poorer treatment outcomes than the general TB population. Limitations of our analysis include the lack of available data on the cascade of care in the private sector and substantial uncertainty regarding the 1-y period prevalence of TB in India. CONCLUSIONS: Increasing case detection is critical to improving outcomes in India's TB cascade of care, especially for smear-negative and MDR TB patients. For new smear-positive patients, pretreatment loss to follow-up and post-treatment TB recurrence are considerable points of attrition that may contribute to ongoing TB transmission. Future multisite studies providing more accurate information on key steps in the public sector TB cascade and extension of this analysis to private sector patients may help to better target interventions and resources for TB control in India.