Prevalence and risk factors for adult pulmonary tuberculosis in a metropolitan city of South India

Evaluation of the National Tuberculosis Program and Tuberculosis Surveillance System, Jordan 2021

Objectives

Evaluate and determine the gaps in the National Tuberculosis Program and Tuberculosis Surveillance System in Jordan.

Methods

A concurrent embedded mixed quantitative/qualitative methods study was conducted to assess the National Tuberculosis Program and Tuberculosis Surveillance System in Jordan. A semi-structured questionnaire was developed based on the Updated CDC Guideline for Evaluating Public Health Surveillance System to collect necessary information from service providers and other stakeholders.

Results

The National Tuberculosis Program and Tuberculosis Surveillance System encounter various gaps and challenges across several critical domains, including infrastructure, human resources, National Tuberculosis Program functions, surveillance system performance, coordination, case findings, and data collection and notification. Regrettably, not all of the Tuberculosis Surveillance System's objectives were successfully achieved in the past. Coordination of tuberculosis services has been repeatedly reported as inadequate. This deficiency manifests in the delay in diagnosing tuberculosis patients and, in some instances, misdiagnoses. The root cause is often traced back to insufficient knowledge of tuberculosis case definitions among healthcare providers at peripheral tuberculosis clinics. Additionally, a structured approach to active case finding is conspicuously absent. Furthermore, the tuberculosis management guidelines remain unfamiliar to many healthcare providers in tuberculosis centers, leaving them inadequately equipped to handle tuberculosis cases effectively. The utilization and analysis of the system's data are also far from optimal. A glaring concern is the delay in tuberculosis case notifications received from the stakeholders involved in the Tuberculosis Surveillance System.

Conclusions

Our study showed different gaps in the National Tuberculosis Program and Tuberculosis Surveillance Systems across several areas. The structure of National Tuberculosis Program and the clinical expertise of human resources do not support tuberculosis elimination. An electronic data collection and notification system is essential to facilitate tuberculosis case detection, reporting, and follow-up. Decision-makers should push the tuberculosis epidemic on the national health agenda. Jordan should focus on allocating national and international resources for tuberculosis control programs.

Operational priorities for engaging with India's private healthcare sector for the control of tuberculosis: a modelling study

OBJECTIVES

To estimate the potential impact of expanding services offered by the Joint Effort for Elimination of Tuberculosis (JEET), the largest private sector engagement initiative for tuberculosis (TB) in India.

DESIGN

We developed a mathematical model of TB transmission dynamics, coupled with a cost model.

SETTING

Ahmedabad and New Delhi, two cities with contrasting levels of JEET coverage.

PARTICIPANTS

Estimated patients with TB in Ahmedabad and New Delhi.

INTERVENTIONS

We investigated the epidemiological impact of expanding three different public-private support agency (PPSA) services: provider recruitment, uptake of cartridge-based nucleic acid amplification tests and uptake of adherence support mechanisms (specifically government supplied fixed-dose combination drugs), all compared with a continuation of current TB services.

RESULTS

Our results suggest that in Delhi, increasing the use of adherence support mechanisms among private providers should be prioritised, having the lowest incremental cost-per-case-averted between 2020 and 2035 of US$170 000 (US$110 000-US$310 000). Likewise in Ahmedabad, increasing provider recruitment should be prioritised, having the lowest incremental cost-per-case averted of US$18 000 (US$12 000-US$29 000).

CONCLUSION

Results illustrate how intervention priorities may vary in different settings across India, depending on local conditions, and the existing degree of uptake of PPSA services. Modelling can be a useful tool for identifying these priorities for any given setting.

Tobacco smoking clusters in households affected by tuberculosis in an individual participant data meta-analysis of national tuberculosis prevalence surveys: Time for household-wide interventions?

Tuberculosis (TB) and non-communicable diseases (NCD) share predisposing risk factors. TB-associated NCD might cluster within households affected with TB requiring shared prevention and care strategies. We conducted an individual participant data meta-analysis of national TB prevalence surveys to determine whether NCD cluster in members of households with TB. We identified eligible surveys that reported at least one NCD or NCD risk factor through the archive maintained by the World Health Organization and searching in Medline and Embase from 1 January 2000 to 10 August 2021, which was updated on 23 March 2023. We compared the prevalence of NCD and their risk factors between people who do not have TB living in households with at least one person with TB (members of households with TB), and members of households without TB. We included 16 surveys (n = 740,815) from Asia and Africa. In a multivariable model adjusted for age and gender, the odds of smoking was higher among members of households with TB (adjusted odds ratio (aOR) 1.23; 95% CI: 1.11-1.38), compared with members of households without TB. The analysis did not find a significant difference in the prevalence of alcohol drinking, diabetes, hypertension, or BMI between members of households with and without TB. Studies evaluating household-wide interventions for smoking to reduce its dual impact on TB and NCD may be warranted. Systematically screening for NCD using objective diagnostic methods is needed to understand the actual burden of NCD and inform comprehensive interventions.

The Predicted Potential Impact of COVID-19 Pandemic on Tuberculosis Epidemic in Tamil Nadu, South India

OBJECTIVE

To estimate the prevalence and incidence of TB before and during the COVID-19 pandemic in Tamil Nadu, south India.

METHODS

In the present study, the effect of COVID-19 epidemiology on the TB epidemic was assessed by the SEIR (Susceptible-Exposed-Infected-Recovered), a compartmental epidemiological model. The model input parameters on compartments of TB and incidence of COVID-19 were collected from the published literature. Based on the data collected, point prevalence and incidence of TB per 100,000 population is calculated with and without COVID-19. A prediction was conducted up to 2025, trend analysis was performed, and a trend chi-square test and chi-square test of independence were used to test the difference between the prevalence with and without COVID-19. R software 2000 (R 4.0.0) was used for analysis.

RESULTS

The TB prevalence without and with COVID-19 decreases from 289 in 2020 to 271 in 2025 and from 289 in 2020 to 269 in 2025, respectively. Similarly, the incidence of TB was decreasing from 144 in 2020 to 135 in 2025 without COVID-19 and 143 in 2020 to 134 in 2025 with COVID-19. Though the TB burden is decreasing over the years, the trend was not statistically significant (p > 0.05). With respect to the district level, the prevalence and incidence of TB with and without COVID-19 is also found to be decreasing over the years. It was also found that the difference in the prevalence and incidence of TB with and without COVID-19 was not statically significant.

CONCLUSION

The results of our study shows that there was an annual decline of around 2% from 2020 to 2025 in the trend of the prevalence and incidence of TB with and without COVID-19. Overall, there is a reduction, but it was not significant, and there is no significant effect of COVID-19 on TB in Tamil Nadu.

The Added Value of Bronchoalveolar Lavage for Pulmonary Tuberculosis Diagnosis in High-Risk Hospitalized Patients with Negative Sputum Samples

Hospitalized patients with a high suspicion of pulmonary tuberculosis (HS-PTB) are isolated until a definite diagnosis can be determined. If doubt remains after negative sputum samples, bronchoscopy with bronchoalveolar lavage (BAL) is often sought. Still, evidence of the added value of BAL in this patient population is scarce. To address this issue, we included consecutive HS-PTB patients with negative sputum samples who underwent BAL between 2017 and 2018. Chest X-rays (CXR) and CT scans were evaluated by a chest radiologist blind to the final diagnosis. Independent predictors for PTB were assessed by multivariate regression, using all positive PTB patients between 2017 and 2019 (by sputum or BAL) as a control group (n = 41). Overall, 42 HS-PTB patients were included (mean age 51 ± 9, 36% female). BAL was a viable diagnostic for PTB in three (7%) cases and for other clinically relevant pathogens in six (14%). Independent predictors for PTB were ≥2 sub-acute symptoms (adjusted OR 3.18, 95% CI 1.04-9.8), CXR upper-lobe consolidation (AOR 8.70, 95% CI 2.5-29), and centrilobular nodules in chest CT (AOR 3.96, 95% CI 1.20-13.0, p = 0.02). In conclusion, bronchoscopy with BAL in hospitalized patients with HS-PTB had a 7% added diagnostic value after negative sputum samples. Our findings highlight specific predictors for PTB diagnosis that could be used in future controlled studies to personalize the diagnostic evaluation.

A study of analysis on prevalence, serological marker and prognosis of tuberculosis in tertiary care hospital

BACKGROUND

Tuberculosis is an infectious disease responsible for a significant cause of ill health. According to the WHO global tuberculosis report 2021. 9.9 million cases fell sick with TB in 2020. Significantly, the prevalence of tuberculosis in India is 25%.

OBJECTIVE

To analyze the prevalence of tuberculosis in the suburban areas of the metropolitan city in South India. To analyze the serological marker and prognosis of tuberculosis among males and females. To determine the importance of molecular testing - PCR confirmation on TB after AFB smear.

METHODS

A retrospective study to analyze 462 patients enrolled by the respiratory medicine department on suspecting pulmonary- 356 (M-264 & F-92) and extra-pulmonary-106 (M-73&F-33) patients and diagnosed Zhiel-Neelsen staining, Mantoux test, Chip-based RT-PCR test, Erythrocyte sedimentation rate, and analyzed serological test such as C-Reactive Protein, Chemiluminescence immune assay.

RESULTS

23 patients were positive in Ziehl-Neelsen staining, 65 were positive in molecular True-Nat PCR test, Mantoux skin test induration in 10 patients, 98 TB Positive patients examined in the serological analysis, 1 & 3 patients reacted in HIV/HBsAg, and HBsAg test respectively, by chemiluminescence immunoassay, 8 PTB and 4 EPTB and 47 non-TB patients were positive in C-reactive protein, 46 TB and 94 non-TB patients detected abnormal values out of these 160 patients in ESR test.

CONCLUSION

The Prevalence of tuberculosis is significantly rising, especially in the middle-aged population. The rapid molecular diagnostics to detect TB are highly sensitive and specific. Serological markers are essential for the analysis of disease prognosis and need to focus on the guidance of DOTS and RNTCP to End TB.

Exploring the Impact of Silicosis Incidence on Tuberculosis Mortality and Morbidity: A Multi-Country Study

INTRODUCTION

There are several risk factors attributed to tuberculosis (TB) mortality and morbidity. There are few studies and systematic reviews showing the association of silicosis and tuberculosis at a country level. Very limited studies have been conducted using multi-country data in studying the association of incidence of silicosis with TB mortality and morbidity. Hence, the aim of this research was to explore the association of incidence of silicosis and other important risk factors with TB mortality and morbidity using multi-country data.

METHODS

Data from 217 WHO region countries were utilized, sourcing TB-related statistics from the Institute of Health Metrics and Evaluation and additional risk factors from the Demographic and Health Survey, Global Burden of Disease, and World Bank for 2019. Regression analysis was conducted to examine the association between silicosis incidence and TB outcomes.

RESULTS

The study found an average silicosis incidence of 121.92 per 100,000 population. Additionally, 62.69% of the sample population are exposed to air pollution from solid fuel cooking. Sanitation access stands at an average of 59.67%. Regression outcomes indicate that while alcohol consumption's influence on TB is not statistically significant, a unit increase in silicosis incidence significantly elevates TB deaths (235.9, p = 0.005), YLL (9399.3, p = 0.011), and YLD (910.8, p = 0.002).

CONCLUSION

The burden of silicosis is found to be one of the important determinants of deaths, YLL, and YLD due to tuberculosis. Country-specific strategies to prevent and control silicosis is a need of the hour.

Association of diabetes, smoking, and alcohol use with subclinical-to-symptomatic spectrum of tuberculosis in 16 countries: an individual participant data meta-analysis of national tuberculosis prevalence surveys

Background

Non-communicable diseases (NCDs) and NCD risk factors, such as smoking, increase the risk for tuberculosis (TB). Data are scarce on the risk of prevalent TB associated with these factors in the context of population-wide systematic screening and on the association between NCDs and NCD risk factors with different manifestations of TB, where ∼50% being asymptomatic but bacteriologically positive (subclinical). We did an individual participant data (IPD) meta-analysis of national and sub-national TB prevalence surveys to synthesise the evidence on the risk of symptomatic and subclinical TB in people with NCDs or risk factors, which could help countries to plan screening activities.

Methods

In this systematic review and IPD meta-analysis, we identified eligible prevalence surveys in low-income and middle-income countries that reported at least one NCD (e.g., diabetes) or NCD risk factor (e.g., smoking, alcohol use) through the archive maintained by the World Health Organization and by searching in Medline and Embase from January 1, 2000 to August 10, 2021. The search was updated on March 23, 2023. We performed a one-stage meta-analysis using multivariable multinomial models. We estimated the proportion of and the odds ratio for subclinical and symptomatic TB compared to people without TB for current smoking, alcohol use, and self-reported diabetes, adjusted for age and gender. Subclinical TB was defined as microbiologically confirmed TB without symptoms of current cough, fever, night sweats, or weight loss and symptomatic TB with at least one of these symptoms. We assessed heterogeneity using forest plots and I2 statistic. Missing variables were imputed through multi-level multiple imputation. This study is registered with PROSPERO (CRD42021272679).

Findings

We obtained IPD from 16 national surveys out of 21 national and five sub-national surveys identified (five in Asia and 11 in Africa, N = 740,815). Across surveys, 15.1%-56.7% of TB were subclinical (median: 38.1%). In the multivariable model, current smoking was associated with both subclinical (OR 1.67, 95% CI 1.27-2.40) and symptomatic TB (OR 1.49, 95% CI 1.34-1.66). Self-reported diabetes was associated with symptomatic TB (OR 1.67, 95% CI 1.17-2.40) but not with subclinical TB (OR 0.92, 95% CI 0.55-1.55). For alcohol drinking ≥ twice per week vs no alcohol drinking, the estimates were imprecise (OR 1.59, 95% CI 0.70-3.62) for subclinical TB and OR 1.43, 95% CI 0.59-3.46 for symptomatic TB). For the association between current smoking and symptomatic TB, I2 was high (76.5% (95% CI 62.0-85.4), while the direction of the point estimates was consistent except for three surveys with wide CIs.

Interpretation

Our findings suggest that current smokers are more likely to have both symptomatic and subclinical TB. These individuals can, therefore, be prioritised for intensified screening, such as the use of chest X-ray in the context of community-based screening. People with self-reported diabetes are also more likely to have symptomatic TB, but the association is unclear for subclinical TB.

Funding

None.

Improving treatment adherence among tuberculosis patients through evening DOTS in Chennai, India

Background Fixed days and timings of service are challenges in the care of patients with tuberculosis (TB). We assessed whether provision of evening DOTS (directly observed treatment, short course) improves treatment outcomes in a city with a working population. Methods We enrolled new adult patients with TB from seven tuberculous units (TUs) in this prospective cohort study. Participants were offered the option of DOTS during the day (8 a.m. to 3:30 p.m.) or evening (4 p.m. to 8 p.m.) and assigned accordingly. Results Of 127 patients enrolled between April and July 2017, 19 (15%) opted for evening DOTS. The number varied between the seven TUs (p=0.002). On an average, antitubercular therapy (ATT) was taken at 9:41 a.m. in the routine and 5:14 p.m. in the evening DOTS centres. Patients who were employed, left residence and returned back at 9:05 a.m. and 6:40 p.m., respectively. Around 96% (104/108) opted for day-time DOTS due to closeness of the centre to their residence. Around 74% (14/19) chose evening DOTS because of time convenience. Around 15% of patients on routine DOTS (16) had unfavourable treatment outcomes. All had favourable outcomes in the evening DOTS. Men were less likely and those withut alcohol disorders were more likely to have treatment success. Conclusion Provision of time convenient services might improve adherence and treatment outcome.

Wastewater surveillance beyond COVID-19: a ranking system for communicable disease testing in the tri-county Detroit area, Michigan, USA

Introduction

Throughout the coronavirus disease 2019 (COVID-19) pandemic, wastewater surveillance has been utilized to monitor the disease in the United States through routine national, statewide, and regional monitoring projects. A significant canon of evidence was produced showing that wastewater surveillance is a credible and effective tool for disease monitoring. Hence, the application of wastewater surveillance can extend beyond monitoring SARS-CoV-2 to encompass a diverse range of emerging diseases. This article proposed a ranking system for prioritizing reportable communicable diseases (CDs) in the Tri-County Detroit Area (TCDA), Michigan, for future wastewater surveillance applications at the Great Lakes Water Authority's Water Reclamation Plant (GLWA's WRP).

Methods

The comprehensive CD wastewater surveillance ranking system (CDWSRank) was developed based on 6 binary and 6 quantitative parameters. The final ranking scores of CDs were computed by summing the multiplication products of weighting factors for each parameter, and then were sorted based on decreasing priority. Disease incidence data from 2014 to 2021 were collected for the TCDA. Disease incidence trends in the TCDA were endowed with higher weights, prioritizing the TCDA over the state of Michigan.

Results

Disparities in incidences of CDs were identified between the TCDA and state of Michigan, indicating epidemiological differences. Among 96 ranked CDs, some top ranked CDs did not present relatively high incidences but were prioritized, suggesting that such CDs require significant attention by wastewater surveillance practitioners, despite their relatively low incidences in the geographic area of interest. Appropriate wastewater sample concentration methods are summarized for the application of wastewater surveillance as per viral, bacterial, parasitic, and fungal pathogens.

Discussion

The CDWSRank system is one of the first of its kind to provide an empirical approach to prioritize CDs for wastewater surveillance, specifically in geographies served by centralized wastewater collection in the area of interest. The CDWSRank system provides a methodological tool and critical information that can help public health officials and policymakers allocate resources. It can be used to prioritize disease surveillance efforts and ensure that public health interventions are targeted at the most potentially urgent threats. The CDWSRank system can be easily adopted to geographical locations beyond the TCDA.

Pre-sensitization with tuberculosis and non-tuberculosis mycobacteria and its impact on TB incidence in different age groups: Chengalpattu BCG trial revisited

Individuals pre-sensitized with Mycobacterium tuberculosis (MTB), non-tuberculosis mycobacteria, and its impact on TB incidence are relatively unexplored in a high TB burden setting. We conducted secondary data analysis of a double-blind, randomized Chengalpattu BCG trial, India. Induration to Purified Protein Derivative (PPD)-S and PPD-B were proxies for exposures to MTB and M. intracellulare respectively. Optimum cut-off for PPD-S and B were determined using Receiver-Operating Characteristic curves and induration ≥12 mm for PPD-S and ≥10 mm for PPD-B were considered strong reaction. Incidence rates of culture positive pulmonary TB per 100,000 person-years (PY) were calculated. Of 270,043 individuals with skin test results, children <14 years (n = 109,383, 64% showed strong-reaction to PPD-B and 17% to PPD-S) and adults between 25 and 34 years (n = 40,292, 98% were strong reactors to PPD-B and 73% to PPD-S). Overall incidence rate was lower in individuals with PPD-S < PPD-B (136, 95% CI: 130-141/100,000 PY) compared to individuals with PPD-S > PPD-B (447, 95% CI: 427-468/100,000 PY). Incidence rates of culture positive pulmonary TB was affected by early age of exposure to cross-reactive mycobacterial antigens represented by PPD-B and exposure to MTB represented by PPD-S during adolescence and early adulthood.

A systematic review and meta-analysis of active case finding for tuberculosis in India

Background

Active case finding (ACF) for tuberculosis (TB) is the cornerstone case-finding strategy in India's national TB policy. However, ACF strategies are highly diverse and pose implementation challenges in routine programming. We reviewed the literature to characterise ACF in India; assess the yield of ACF for different risk groups, screening locations, and screening criteria; and estimate losses to follow-up (LTFU) in screening and diagnosis.

Methods

We searched PubMed, EMBASE, Scopus, and the Cochrane library to identify studies with ACF for TB in India from November 2010 to December 2020. We calculated 1) weighted mean number needed to screen (NNS) stratified by risk group, screening location, and screening strategy; and 2) the proportion of screening and pre-diagnostic LTFU. We assessed risk of bias using the AXIS tool for cross-sectional studies.

Findings

Of 27,416 abstracts screened, we included 45 studies conducted in India. Most studies were from southern and western India and aimed to diagnose pulmonary TB at the primary health level in the public sector after screening. There was considerable heterogeneity in risk groups screened and ACF methodology across studies. Of the 17 risk groups identified, the lowest weighted mean NNS was seen in people with HIV (21, range 3-89, n=5), tribal populations (50, range 40-286, n=3), household contacts of people with TB (50, range 3-undefined, n=12), people with diabetes (65, range 21-undefined, n=3), and rural populations (131, range 23-737, n=5). ACF at facility-based screening (60, range 3-undefined, n=19) had lower weighted mean NNS than at other screening locations. Using the WHO symptom screen (135, 3-undefined, n=20) had lower weighted mean NNS than using criteria of abnormal chest x-ray or any symptom. Median screening and pre-diagnosis loss-to-follow-up was 6% (IQR 4.1%, 11.3%, range 0-32.5%, n=12) and 9.5% (IQR 2.4%, 34.4%, range 0-86.9%, n=27), respectively.

Interpretation

For ACF to be impactful in India, its design must be based on contextual understanding. The narrow evidence base available currently is insufficient for effectively targeting ACF programming in a large and diverse country. Achieving case-finding targets in India requires evidence-based ACF implementation.

Funding

WHO Global TB Programme.

Role of genetic variations of DNA damage response pathway genes and heat-shock proteins in increased head and neck cancer risk

Aim: The present study was designed to evaluate the role of DNA damage response pathway genes and heat-shock proteins in head and neck cancer (HNC) risk. Methods: For this purpose, two study cohorts were used. Cohort 1 (blood samples of 250 HNC patients and 250 controls) was used for polymorphism screening of selected genes using tetra-primer amplification refractory mutation system-polymerase chain (Tetra-ARMS PCR). Cohort 2 (200 HNC tumors and adjacent controls) was used for expression analysis, using quantitative PCR. Results: Analysis showed that mutant allele frequency of selected polymorphisms was found associated with increased HNC risk. Expression analysis showed the significant deregulation of selected genes in patients. Conclusion: The present study showed that selected genes (CHK1, CHK2, HSP70 and HSP90) can act as good diagnostic/prognostic markers in HNC.

Combating Salinity Through Natural Plant Extracts Based Biostimulants: A Review

Enhanced crop growth and yield are the recurring concerns in agricultural field, considering the soaring world population and climate change. Abiotic stresses are one of the major limiting factors for constraining crop production, for several economically important horticultural crops, and contribute to almost 70% of yield gap. Salt stress is one of these unsought abiotic stresses that has become a consistent problem in agriculture over the past few years. Salinity further induces ionic, osmotic, and oxidative stress that result in various metabolic perturbations (including the generation of reactive oxygen, carbonyl, and nitrogen species), reduction in water potential (ψw), distorted membrane potential, membrane injury, altered rates of photosynthesis, leaf senescence, and reduced nitrogen assimilation, among others); thereby provoking a drastic reduction in crop growth and yield. One of the strategies to mitigate salt stress is the use of natural plant extracts (PEs) instead of chemical fertilizers, thus limiting water, soil, and environmental pollution. PEs mainly consist of seeds, roots, shoots, fruits, flowers, and leaves concentrates employed either individually or in mixtures. Since PEs are usually rich in bioactive compounds (e.g., carotenoids, flavonoids, phenolics, etc.), therefore they are effective in regulating redox metabolism, thereby promoting plant growth and yield. However, various factors like plant growth stage, doses applied, application method, soil, and environmental conditions may greatly influence their impact on plants. PEs have been reported to enhance salt tolerance in plants primarily through modulation of signaling signatures and pathways (e.g., Na+, ANNA4, GIPC, SOS3, and SCaBP8 Ca2+ sensors, etc.), and regulation of redox machinery [e.g., superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), non-specific peroxidase (POX), glutathione peroxidase (GPX), peroxiredoxin (Prx), ascorbic acid (AsA), glutathione (GSH), α-tocopherol, etc.]. The current study highlights the role of PEs in terms of their sources, methods of preparation, and mode of action with subsequent physiological changes induced in plants against salinity. However, an explicit mode of action of PEs remains nebulous, which might be explicated utilizing transcriptomics, proteomics, metabolomics, and bioinformatics approaches. Being ecological and economical, PEs might pave the way for ensuring the food security in this challenging era of climate change.

Host Metabolic Changes during Mycobacterium Tuberculosis Infection Cause Insulin Resistance in Adult Mice

Tuberculosis (TB) is a highly infectious bacterial disease that primarily attacks the lungs. TB is manifested either as latent TB infection (LTBI) or active TB disease, the latter posing a greater threat to life. The risk of developing active TB disease from LTBI is three times higher in individuals with type 2 diabetes mellitus (T2DM). The association between TB and T2DM is becoming more prominent as T2DM is rapidly increasing in settings where TB is endemic. T2DM is a chronic metabolic disorder characterized by elevated blood glucose, insulin resistance, and relative insulin deficiency. Insulin resistance and stress-induced hyperglycemia have been shown to be increased by TB and to return to normal upon treatment. Previously, we demonstrated that adipocytes (or fat tissue) regulate pulmonary pathology, inflammation, and Mycobacterium tuberculosis (Mtb) load in a murine model of TB. Metabolic disturbances of adipose tissue and/or adipocyte dysfunction contribute to the pathogenesis of T2DM. Thus, pathological adipocytes not only regulate pulmonary pathology, but also increase the risk for T2DM during TB infection. However, the cellular and molecular mechanisms driving the interaction between hyperglycemia, T2DM and TB remain poorly understood. Here, we report the impact of Mtb infection on the development of insulin resistance in mice fed on a regular diet (RD) versus high-fat diet (HFD) and, conversely, the effect of hyperglycemia on pulmonary pathogenesis in juvenile and adult mouse models. Overall, our study demonstrated that Mtb persists in adipose tissue and that Mtb infection induces irregular adipocyte lipolysis and loss of fat cells via different pathways in RD- and HFD-fed mice. In RD-fed mice, the levels of TNFα and HSL (hormone sensitive lipase) play an important role whereas in HFD-fed mice, ATGL (adipose triglyceride lipase) plays a major role in regulating adipocyte lipolysis and apoptosis during Mtb infection in adult mice. We also showed that Mtb infected adult mice that were fed an RD developed insulin resistance similar to infected adult mice that were overweight due to a HFD diet. Importantly, we found that a consequence of Mtb infection was increased lipid accumulation in the lungs, which altered cellular energy metabolism by inhibiting major energy signaling pathways such as insulin, AMPK and mToR. Thus, an altered balance between lipid metabolism and glucose metabolism in adipose tissue and other organs including the lungs may be an important component of the link between Mtb infection and subsequent metabolic syndrome.

Measuring Tuberculosis Medication Adherence: A Comparison of Multiple Approaches in Relation to Urine Isoniazid Metabolite Testing Within a Cohort Study in India

Background

Nonadherence to tuberculosis medications is associated with poor outcomes. However, measuring adherence in practice is challenging. In this study, we evaluated the accuracy of multiple tuberculosis adherence measures.

Methods

We enrolled adult Indians with drug-susceptible tuberculosis who were monitored using 99DOTS, a cellphone-based technology. During an unannounced home visit with each participant, we assessed adherence using a pill estimate, 4-day dose recall, a last missed dose question, and urine isoniazid metabolite testing. We estimated the area under the receiver operating characteristic curve (AUC) for each alternate measure in comparison to urine testing. 99DOTS data were analyzed using patient-reported doses alone and patient- and provider-reported doses, the latter reflecting how 99DOTS is implemented in practice. We assessed each measure's operating characteristics, with particular interest in specificity-that is, the percentage of participants detected as being nonadherent by each alternate measure, among those who were nonadherent by urine testing.

Results

Compared with urine testing, alternate measures had the following characteristics: 99DOTS patient-reported doses alone (area under the curve [AUC], 0.65; specificity, 70%; 95% CI, 58%-81%), 99DOTS patient- and provider-reported doses (AUC, 0.61; specificity, 33%; 95% CI, 22%-45%), pill estimate (AUC, 0.55; specificity, 21%; 95% CI, 12%-32%), 4-day recall (AUC, 0.60; specificity, 23%; 95% CI, 14%-34%), and last missed dose question (AUC, 0.65; specificity, 52%; 95% CI, 40%-63%).

Conclusions

Alternate measures missed detecting at least 30% of people who were nonadherent by urine testing. The last missed dose question performed similarly to 99DOTS using patient-reported doses alone. Tuberculosis programs should evaluate the feasibility of integrating more accurate, objective measures, such as urine testing, into routine care.

Achieving a "step change" in the tuberculosis epidemic through comprehensive community-wide intervention: a model-based analysis

BACKGROUND

Global progress towards reducing tuberculosis (TB) incidence and mortality has consistently lagged behind the World Health Organization targets leading to a perception that large reductions in TB burden cannot be achieved. However, several recent and historical trials suggest that intervention efforts that are comprehensive and intensive can have a substantial epidemiological impact. We aimed to quantify the potential epidemiological impact of an intensive but realistic, community-wide campaign utilizing existing tools and designed to achieve a "step change" in the TB burden.

METHODS

We developed a compartmental model that resembled TB transmission and epidemiology of a mid-sized city in India, the country with the greatest absolute TB burden worldwide. We modeled the impact of a one-time, community-wide screening campaign, with treatment for TB disease and preventive therapy for latent TB infection (LTBI). This one-time intervention was followed by the strengthening of the tuberculosis-related health system, potentially facilitated by leveraging the one-time campaign. We estimated the tuberculosis cases and deaths that could be averted over 10 years using this comprehensive approach and assessed the contributions of individual components of the intervention.

RESULTS

A campaign that successfully screened 70% of the adult population for active and latent tuberculosis and subsequently reduced diagnostic and treatment delays and unsuccessful treatment outcomes by 50% was projected to avert 7800 (95% range 5450-10,200) cases and 1710 (1290-2180) tuberculosis-related deaths per 1 million population over 10 years. Of the total averted deaths, 33.5% (28.2-38.3) were attributable to the inclusion of preventive therapy and 52.9% (48.4-56.9) to health system strengthening.

CONCLUSIONS

A one-time, community-wide mass campaign, comprehensively designed to detect, treat, and prevent tuberculosis with currently existing tools can have a meaningful and long-lasting epidemiological impact. Successful treatment of LTBI is critical to achieving this result. Health system strengthening is essential to any effort to transform the TB response.

Engaging with the private healthcare sector for the control of tuberculosis in India: cost and cost-effectiveness

Background

The control of tuberculosis (TB) in India is complicated by the presence of a large, disorganised private sector where most patients first seek care. Following pilots in Mumbai and Patna (two major cities in India), an initiative known as the ‘Public–Private Interface Agency’ (PPIA) is now being expanded across the country. We aimed to estimate the cost-effectiveness of scaling up PPIA operations, in line with India’s National Strategic Plan for TB control.

Methods

Focusing on Mumbai and Patna, we collected cost data from implementing organisations in both cities and combined this data with models of TB transmission dynamics. Estimating the cost per disability adjusted life years (DALY) averted between 2014 (the start of PPIA scale-up) and 2025, we assessed cost-effectiveness using two willingness-to-pay approaches: a WHO-CHOICE threshold based on per-capita economic productivity, and a more stringent threshold incorporating opportunity costs in the health system.

Findings

A PPIA scaled up to ultimately reach 50% of privately treated TB patients in Mumbai and Patna would cost, respectively, US$228 (95% uncertainty interval (UI): 159 to 320) per DALY averted and US$564 (95% uncertainty interval (UI): 409 to 775) per DALY averted. In Mumbai, the PPIA would be cost-effective relative to all thresholds considered. In Patna, if focusing on adherence support, rather than on improved diagnosis, the PPIA would be cost-effective relative to all thresholds considered. These differences between sites arise from variations in the burden of drug resistance: among the services of a PPIA, improved diagnosis (including rapid tests with genotypic drug sensitivity testing) has greatest value in settings such as Mumbai, with a high burden of drug-resistant TB.

Conclusions

To accelerate decline in TB incidence, it is critical first to engage effectively with the private sector in India. Mechanisms such as the PPIA offer cost-effective ways of doing so, particularly when tailored to local settings.

Prevalence of bacteriologically confirmed pulmonary tuberculosis and associated risk factors: A community survey in Thirvallur District, south India

BACKGROUND

Tuberculosis (TB) prevalence surveys add to the active case detection in the community level burden of TB both national and regional levels. The aim of this study was to assess the prevalence of bacteriologically confirmed pulmonary tuberculosis (PTB) in the community.

METHODS

Household community-based tuberculosis disease survey was conducted targeting 69054 population from 43 villages of 5 blocks in Tiruvallure district adopting cluster sampling methodology of ≥15 years old adult rural population of South India during 2015-2018. All eligible individuals with suspected symptoms of PTB were screened with chest X-ray. Two sputum specimens (one spot and the other early morning sample) were collected for M.tb smear and culture examination. Conversely demographical, smoking and alcohol drinking habits information were also collected to explore the risk factor. Stepwise logistic regression was employed to associate risk factors for PTB.

RESULTS

A total of 62494 were screened among 69054 eligible population, of whom 6340 were eligible for sputum specimen collection. Sputum for M.tb smear and culture examination were collected in 93% of participants. The derived prevalence of PTB was 307/100000 population (smear-positive 130; culture positive 277). As expected that PTB has decreased substantially compared to preceding surveys and it showed that older age, male, low BMI, diabetes, earlier history of TB and alcohol users were significantly associated (p < .0001) with an increased risk of developing PTB.

CONCLUSION

Upshot of the active survey has established a reduction in the prevalence of PTB in the rural area which can be accredited to better programmatic implementation and success of the National TB Control Programme in this district. It also has highlighted the need for risk reduction interventions accelerate faster elimination of TB.

Emerging and Public Health Challenges Existing in Gestational Diabetes Mellitus and Diabetes in Pregnancy

We review the evidence available worldwide on the various challenges in the screening, management, prevention of gestational diabetes mellitus and diabetes in pregnancy. The use of multiple screening and diagnostic tests prescribed by numerous guidelines is challenging for practitioners. Also, sociocultural, demographic and economic challenges affect the prevention and care. Life-course perspectives need to be adopted, as well as an integrated approach in public health care is essential. Tackling these challenges at each phase of life-course, with development and adherence to the country-specific guidelines by practitioners can decrease the burden of gestational diabetes mellitus and diabetes in pregnancy.

Heterogeneity of non-cystic-fibrosis bronchiectasis in multiethnic Singapore: A prospective cohort study at a tertiary pulmonology centre

Introduction: Non-cystic fibrosis bronchiectasis (NCFB) is a highly heterogenous disease. We describe the clinical characteristics of NCFB patients and evaluate the performance of Bronchiectasis Severity Index (BSI) in predicting mortality. Methods: Patients attending the bronchiectasis clinic between August 2015 and April 2020 with radiologically proven bronchiectasis on computed tomography were recruited. Clinical characteristics, spirometry, radiology, microbiology and clinical course over a median period of 2.4 years is presented. Results: A total of 168 patients were enrolled in this prospective cohort study. They were predominantly women (67.8%), Chinese (87.5%) and never-smokers (76.9%). Median age of diagnosis was 64 years (interquartile range 56–71) and the most common aetiology was “idiopathic” bronchiectasis (44.6%). Thirty-nine percent had normal spirometries. Compared to female patients, there were more smokers among the male patients (53.8% versus 8.5%, P<0.001) and a significantly larger proportion with post-tuberculous bronchiectasis (37.0% vs 15.8%, P=0.002). Fifty-five percent of our cohort had a history of haemoptysis. Lower body mass index, presence of chronic obstructive pulmonary disease, ever-smoker status, modified Reiff score, radiological severity and history of exacerbations were risk factors for mortality. Survival was significantly shorter in patients with severe bronchiectasis (BSI>9) compared to those with mild or moderate disease (BSI<9). The hazard ratio for severe disease (BSI>9) compared to mild disease (BSI 0–4) was 14.8 (confidence interval 1.929–114.235, P=0.01). Conclusion: The NCFB cohort in Singapore has unique characteristics with sex differences. Over half the patients had a history of haemoptysis. The BSI score is a useful predictor of mortality in our population. Keywords: Bronchiectasis, exacerbations, gender, haemoptysis, mortality, Reiff score, sex

Understanding why at-risk population segments do not seek care for tuberculosis: a precision public health approach in South India

INTRODUCTION

Delaying care-seeking for tuberculosis (TB) symptoms is a major contributor to mortality, leading to worse outcomes and spread. To reduce delays, it is essential to identify barriers to care-seeking and target populations most at risk of delaying. Previous work identifies barriers only in people within the health system, often long after initial care-seeking.

METHODS

We conducted a community-based survey of 84 625 households in Chennai, India, to identify 1667 people with TB-indicative symptoms in 2018-2019. Cases were followed prospectively to observe care-seeking behaviour. We used a comprehensive survey to identify care-seeking drivers, then performed multivariate analyses to identify care-seeking predictors. To identify profiles of individuals most at risk to delay care-seeking, we segmented the sample using unsupervised clustering. We then estimated the per cent of the TB-diagnosed population in Chennai in each segment.

RESULTS

Delayed care-seeking characteristics include smoking, drinking, being employed, preferring different facilities than the community, believing to be at lower risk of TB and believing TB is common. Respondents who reported fever or unintended weight loss were more likely to seek care. Clustering analysis revealed seven population segments differing in care-seeking, from a retired/unemployed/disabled cluster, where 70% promptly sought care, to a cluster of employed men who problem-drink and smoke, where only 42% did so. Modelling showed 54% of TB-diagnosed people who delay care-seeking might belong to the latter segment, which is most likely to acquire TB and least likely to promptly seek care.

CONCLUSION

Interventions to increase care-seeking should move from building general awareness to addressing treatment barriers such as lack of time and low-risk perception. Care-seeking interventions should address specific beliefs through a mix of educational, risk perception-targeting and social norms-based campaigns. Employed men who problem-drink and smoke are a prime target for interventions. Reducing delays in this group could dramatically reduce TB spread.

Potential Drugs for the Treatment of COVID-19: Synthesis, Brief History and Application

Coronaviruses (CoVs) belonging to the Betacoronavirus group, an unusually large RNA genome, are characterized by club-like spikes that project from their surface. An outbreak of a novel coronavirus 2019 (nCOVID-19) showing a unique replication strategy and infection has posed a significant threat to international health and the economy around the globe. Scientists around the world are investigating few previously used clinical drugs for the treatment of COVID-19. This review provides synthesis and mode of action of recently investigated drugs like Chloroquine, Hydroxychloroquine, Ivermectin, Selamectin, Remdesivir, Baricitinib, Darunavir, Favipiravir, Lopinavir/ritonavir and Mefloquine hydrochloride that constitute an option for COVID-19 treatment.

Acceptability of the Medication Event Reminder Monitor for Promoting Adherence to Multidrug-Resistant Tuberculosis Therapy in Two Indian Cities: Qualitative Study of Patients and Health Care Providers

Background

Patients with multidrug-resistant tuberculosis (MDR-TB) face challenges adhering to medications, given that treatment is prolonged and has a high rate of adverse effects. The Medication Event Reminder Monitor (MERM) is a digital pillbox that provides pill-taking reminders and facilitates the remote monitoring of medication adherence.

Objective

This study aims to assess the MERM’s acceptability to patients and health care providers (HCPs) during pilot implementation in India’s public sector MDR-TB program.

Methods

From October 2017 to September 2018, we conducted qualitative interviews with patients who were undergoing MDR-TB therapy and were being monitored with the MERM and HCPs in the government program in Chennai and Mumbai. Interview transcripts were independently coded by 2 researchers and analyzed to identify the emergent themes. We organized findings by using the Unified Theory of Acceptance and Use of Technology (UTAUT), which outlines 4 constructs that predict technology acceptance—performance expectancy, effort expectancy, social influence, and facilitating conditions.

Results

We interviewed 65 patients with MDR-TB and 10 HCPs. In patient interviews, greater acceptance of the MERM was related to perceptions that the audible and visual reminders improved medication adherence and that remote monitoring reduced the frequency of clinic visits (performance expectancy), that the device’s organization and labeling of medications made it easier to take them correctly (effort expectancy), that the device facilitated positive family involvement in the patient’s care (social influences), and that remote monitoring made patients feel more cared for by the health system (facilitating conditions). Lower patient acceptance was related to problems with the durability of the MERM’s cardboard construction and difficulties with portability and storage because of its large size (effort expectancy), concerns regarding stigma and the disclosure of patients’ MDR-TB diagnoses (social influences), and the incorrect understanding of the MERM because of suboptimal counseling (facilitating conditions). In their interviews, HCPs reported that MERM implementation resulted in fewer in-person interactions with patients and thus allowed HCPs to dedicate more time to other tasks, which improved job satisfaction.

Conclusions

Several features of the MERM support its acceptability among patients with MDR-TB and HCPs, and some barriers to patient use could be addressed by improving the design of the device. However, some barriers, such as disease-related stigma, are more difficult to modify and may limit use of the MERM among some patients with MDR-TB. Further research is needed to assess the accuracy of MERM for measuring adherence, its effectiveness for improving treatment outcomes, and patients’ sustained use of the device in larger scale implementation.

R, P S, S A, Dusthakeer A, J B, K. Chadha V, G. S. T, Raghunath D, Das M, Khan AM, Kaur H. 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.

Understanding Nonadherence to Tuberculosis Medications in India Using Urine Drug Metabolite Testing: A Cohort Study

BACKGROUND

Poor adherence to tuberculosis (TB) treatment is associated with disease recurrence and death. Little research has been conducted in India to understand TB medication nonadherence.

METHODS

We enrolled adult drug-susceptible TB patients, approximately half of whom were people with human immunodeficiency virus (PWH), in Chennai, Vellore, and Mumbai. We conducted a single unannounced home visit to administer a survey assessing reasons for nonadherence and collect a urine sample that was tested for isoniazid content. We described patient-reported reasons for nonadherence and identified factors associated with nonadherence (ie, negative urine test) using multivariable logistic regression. We also assessed the association between nonadherence and treatment outcomes.

RESULTS

Of 650 participants in the cohort, 77 (11.8%) had a negative urine test. Nonadherence was independently associated with daily wage labor (adjusted odds ratio [aOR], 2.7; confidence interval [CI], 1.1-6.5; P = .03), the late continuation treatment phase (aOR, 2.0; CI, 1.1-3.9; P = .03), smear-positive pulmonary disease (aOR, 2.1; CI, 1.1-3.9; P = .03), alcohol use (aOR, 2.5; CI, 1.2-5.2; P = .01), and spending ≥30 minutes collecting medication refills (aOR, 6.6; CI, 1.5-29.5; P = .01). People with HIV reported greater barriers to collecting medications than non-PWH. Among 167 patients reporting missing doses, reported reasons included traveling from home, forgetting, feeling depressed, and running out of pills. The odds of unfavorable treatment outcomes were 4.0 (CI, 2.1-7.6) times higher among patients with nonadherence (P < .0001).

CONCLUSION

Addressing structural and psychosocial barriers will be critical to improve TB treatment adherence in India. Urine isoniazid testing may help identify nonadherent patients to facilitate early intervention during treatment.

Long-term exposure to indoor air pollution and risk of tuberculosis

Indoor air pollution (IAP) is a recognized risk factor for various diseases. This paper examines the role of indoor solid fuel exposure in the risk of mycobacterium tuberculosis (TB) in Delhi Metropolitan, India. Using a cross-sectional design, subjects were screened for a history of active TB and lifelong exposure to IAP sources, such as solid fuel burning and kerosene. The TB prevalence rate in the study area was 1117 per 100 000 population. Every year, increase in solid fuel exposure was associated with a three percent higher likelihood of a history of active TB. Subjects exposed to solid fuel and kerosene use for both heating home and cooking showed significant associations with TB. Age, household expenditure (a proxy of income), lung function, and smoking also showed significant associations with TB. Smokers and solid fuel-exposed subjects were four times more likely to have a history of active TB than non-smoker and unexposed subjects. These finding calls strategies to mitigate solid fuel exposure, such as use of clean cookstove and ventilation, to mitigate the risk of TB which aligns with the United Nations' goal of "End TB by 2030."

Sex-related differences in smear-positive pulmonary tuberculosis patients in Kuala Lumpur, Malaysia: Prevalence and associated factors

Smear-positive pulmonary tuberculosis (PTB) is more infectious compared to smear-negative PTB and have great significance for epidemiology and infection control. The prevalence of smear-positive PTB rarely affects males and females equally. Hence, we aimed to identify the sex-related differences in the prevalence of smear-positive PTB and its associated factors in Kuala Lumpur, Malaysia. A cross-sectional study was conducted using data from the National Tuberculosis Information System (TBIS) from 1 January, 2015, to 31 December, 2019. The study population was selected using simple random sampling from the list of registered PTB patients in TBIS. The criteria for inclusion were all Malaysian adults aged ≥18 years residing in Kuala Lumpur and registered as PTB in TBIS. Factors associated with smear-positive PTB in male and female patients were determined using multiple logistic regression analysis. Overall prevalence of smear-positive PTB was 68.6%, and male patients predominated (71%). The male:female prevalence ratio of smear-positive PTB was 2.4:1. Male patients who worked as machine operators and elementary workers (adjusted odds ratio (aOR) 2.23, 95% confidence interval (CI) 1.24-4.02, p = 0.007), were self-employed (aOR 2.58, 95% CI 1.46-4.56, p = 0.001), lived in a residence categorized as 'other' (aOR 2.49, 95% CI 1.28-4.86, p = 0.007) and were smokers (aOR 1.37, 95% CI 1.01-1.87, p = 0.045) had higher odds for smear-positive PTB. Meanwhile, female patients with diabetes mellitus had higher odds for smear-positive PTB (aOR 1.92, 95% CI 1.05-3.54, p = 0.035), while female patients who were healthcare workers had lower odds (aOR 0.33, 95% CI 0.12, 0.94, p = 0.039). The prevalence of smear-positive PTB is higher in males compared to females. The factors associated with smear-positive PTB differed based on sex. The current TB control program, especially on smear-positive PTB, should likely be strategized and stratified by sex.

Sensitivity and specificity of tuberculosis signs and symptoms screening and adjunct role of social pathology characteristics in predicting bacteriologically confirmed tuberculosis in Myanmar

BACKGROUND

Globally, using tuberculosis signs and symptoms (TB-SS) as a screening tool has become less important due to its low sensitivity and specificity. We analyzed data from the Myanmar National Tuberculosis (TB) prevalence survey in 2010. The various TB screening models were developed to predict TB by using logistic regression analysis, and their performance on TB prediction was compared by the measures of overall performance, calibration and discrimination ability, and sensitivity and specificity to determine whether social pathology characteristics could be used as a TB screening tool.

RESULTS

Among 51,367 participants, 311 (0.6%) had bacteriologically confirmed TB, of which 37.2% were asymptomatic and 2% had a normal chest X-ray. Out of 32 various combinations of signs and symptoms, having any signs and symptoms gave the best sensitivity of 59.8% and specificity of 67.2%, but chest X-ray (CXR) alone gave the highest sensitivity (95.1%) and specificity (86.3%). The next best combination was cough only with a sensitivity of 24.4% and specificity of 85%. Other combinations had poor sensitivity (< 10%). Among various TB screening models, the overall performance R2 was higher in the combined models of social pathology and TB signs and symptoms as well as the social pathology model, compared to TB-SS models (> 10% versus < 3%), although all TB screening models were perfect to predict TB (Brier score = 0). The social pathology model shows a better calibration, more closer to 45° line of calibration plot with Hosmer-Lemeshow test p value = 0.787, than the combined models while it had a better discrimination ability in area under the curve, AUC = 80.4%, compared to TB-SS models with any signs and symptoms, AUC = 63.5% and with any cough, AUC = 57.1% (DeLong p value = 0.0001). Moreover, at the propensity score cutoff value ≥ 0.0053, the combined and social pathology models had sensitivity of ~ 80% and specificity of ~ 70%. The highest population attributable fraction to predict TB by social pathology characteristics was male gender (42.6%), age ≥ 55 years (31.0%), and underweight (30.4%).

CONCLUSION

Over one-third of bacteriologically confirmed TB was asymptomatic. The conventional TB-SS screening tool using any TB signs and symptoms had a lower sensitivity and specificity compared to CXR and social pathology screening tools. The social pathology characteristics as TB screening tool had good calibration and can improve the discrimination ability to predict TB than TB-SS screenings and should be encouraged.

Trade-offs between cost and accuracy in active case finding for tuberculosis: A dynamic modelling analysis

BACKGROUND

Active case finding (ACF) may be valuable in tuberculosis (TB) control, but questions remain about its optimum implementation in different settings. For example, smear microscopy misses up to half of TB cases, yet is cheap and detects the most infectious TB cases. What, then, is the incremental value of using more sensitive and specific, yet more costly, tests such as Xpert MTB/RIF in ACF in a high-burden setting?

METHODS AND FINDINGS

We constructed a dynamic transmission model of TB, calibrated to be consistent with an urban slum population in India. We applied this model to compare the potential cost and impact of 2 hypothetical approaches following initial symptom screening: (i) 'moderate accuracy' testing employing a microscopy-like test (i.e., lower cost but also lower accuracy) for bacteriological confirmation and (ii) 'high accuracy' testing employing an Xpert-like test (higher cost but also higher accuracy, while also detecting rifampicin resistance). Results suggest that ACF using a moderate-accuracy test could in fact cost more overall than using a high-accuracy test. Under an illustrative budget of US$20 million in a slum population of 2 million, high-accuracy testing would avert 1.14 (95% credible interval 0.75-1.99, with p = 0.28) cases relative to each case averted by moderate-accuracy testing. Test specificity is a key driver: High-accuracy testing would be significantly more impactful at the 5% significance level, as long as the high-accuracy test has specificity at least 3 percentage points greater than the moderate-accuracy test. Additional factors promoting the impact of high-accuracy testing are that (i) its ability to detect rifampicin resistance can lead to long-term cost savings in second-line treatment and (ii) its higher sensitivity contributes to the overall cases averted by ACF. Amongst the limitations of this study, our cost model has a narrow focus on the commodity costs of testing and treatment; our estimates should not be taken as indicative of the overall cost of ACF. There remains uncertainty about the true specificity of tests such as smear and Xpert-like tests in ACF, relating to the accuracy of the reference standard under such conditions.

CONCLUSIONS

Our results suggest that cheaper diagnostics do not necessarily translate to less costly ACF, as any savings from the test cost can be strongly outweighed by factors including false-positive TB treatment, reduced sensitivity, and foregone savings in second-line treatment. In resource-limited settings, it is therefore important to take all of these factors into account when designing cost-effective strategies for ACF.

Association between indoor air pollution, tobacco smoke and tuberculosis: an updated systematic review and meta-analysis

OBJECTIVE

This study aims to further quantify evidence of the association between exposure to indoor air pollution (IAP), tobacco smoke etc., on the one hand and the risk of contracting tuberculosis (TB) on the other.

STUDY DESIGN

This was a systematic review and meta-analysis of articles published between June 2014 and February 2020 in PubMed, Web of Science, among others.

METHODS

We only included studies that controlled for confounders, screened both the exposed and unexposed study participants, and passive smoking studies that limited the study population to non-smokers. Quality of studies was assessed using the Newcastle-Ottawa scale. The analysis was conducted using STATA, and pooled effect sizes were calculated using the random-effects model, and heterogeneity was tested for using the Cochran Q test and I2 statistic.

RESULTS

A total of 26 articles were included in the final analysis. There was an increased risk of contracting TB among people exposed to IAP (risk ratio [RR] = 1.68, 95% confidence interval [CI] 1.108-2.542). We also observed a two-fold increase in the risk of contracting TB from exposure to secondhand tobacco smoke (RR = 2.15, 95%CI 1.419-3.242). Tobacco smoking doubled the risk of contracting TB (RR = 2.67, 95%CI 2.017-3.527). Furthermore, studies that used microbiological tests showed a higher RR compared to those that used other TB diagnostic methods.

CONCLUSION

Exposure to IAP and secondhand tobacco smoke increases the risk of contracting TB. Various disease prevention campaigns should include IAP awareness and encourage a shift to cleaner sources of energy.

Explaining Differences in the Acceptability of 99DOTS, a Cell Phone-Based Strategy for Monitoring Adherence to Tuberculosis Medications: Qualitative Study of Patients and Health Care Providers

Background

99DOTS is a cell phone–based strategy for monitoring tuberculosis (TB) medication adherence that has been rolled out to more than 150,000 patients in India’s public health sector. A considerable proportion of patients stop using 99DOTS during therapy.

Objective

This study aims to understand reasons for variability in the acceptance and use of 99DOTS by TB patients and health care providers (HCPs).

Methods

We conducted qualitative interviews with individuals taking TB therapy in the government program in Chennai and Vellore (HIV-coinfected patients) and Mumbai (HIV-uninfected patients) across intensive and continuation treatment phases. We conducted interviews with HCPs who provide TB care, all of whom were involved in implementing 99DOTS. Interviews were transcribed, coded using a deductive approach, and analyzed with Dedoose 8.0.35 software (SocioCultural Research Consultants, LLC). The findings of the study were interpreted using the unified theory of acceptance and use of technology, which highlights 4 constructs associated with technology acceptance: performance expectancy, effort expectancy, social influences, and facilitating conditions.

Results

We conducted 62 interviews with patients with TB, of whom 30 (48%) were HIV coinfected, and 31 interviews with HCPs. Acceptance of 99DOTS by patients was variable. Greater patient acceptance was related to perceptions of improved patient-HCP relationships from increased phone communication, TB pill-taking habit formation due to SMS text messaging reminders, and reduced need to visit health facilities (performance expectancy); improved family involvement in TB care (social influences); and from 99DOTS leading HCPs to engage positively in patients’ care through increased outreach (facilitating conditions). Lower patient acceptance was related to perceptions of reduced face-to-face contact with HCPs (performance expectancy); problems with cell phone access, literacy, cellular signal, or technology fatigue (effort expectancy); high TB- and HIV-related stigma within the family (social influences); and poor counseling in 99DOTS by HCPs or perceptions that HCPs were not acting upon adherence data (facilitating conditions). Acceptance of 99DOTS by HCPs was generally high and related to perceptions that the 99DOTS adherence dashboard and patient-related SMS text messaging alerts improve quality of care, the efficiency of care, and the patient-HCP relationship (performance expectancy); that the dashboard is easy to use (effort expectancy); and that 99DOTS leads to better coordination among HCPs (social influences). However, HCPs described suboptimal facilitating conditions, including inadequate training of HCPs in 99DOTS, unequal changes in workload, and shortages of 99DOTS medication envelopes.

Conclusions

In India’s government TB program, 99DOTS had high acceptance by HCPs but variable acceptance by patients. Although some factors contributing to suboptimal patient acceptance are modifiable, other factors such as TB- and HIV-related stigma and poor cell phone accessibility, cellular signal, and literacy are more difficult to address. Screening for these barriers may facilitate targeting of 99DOTS to patients more likely to use this technology.

Is routine pre-entry chest radiograph necessary in a high tuberculosis prevalence country?

CONTEXT

Chest radiographs have been used worldwide as a screening tool before employment and training, by various healthcare and other government and nongovernment institutions. Many studies done in the past have demonstrated a relatively low yield for tuberculosis detection and therefore, the authors have questioned this practice.

AIMS

To compare the value of the preadmission/employment chest radiograph in two groups, namely, those who have been previously exposed to a healthcare setting (post-exposure group) and those who have not been exposed (pre-exposure group) and to determine if there is a significant difference in tuberculosis detection between these two groups.

SETTINGS AND DESIGN

A retrospective review of the reports of the chest radiographs of all candidates appearing for admission to various undergraduate and postgraduate courses in our institute between 2014 and 2017 was performed.

MATERIALS AND METHODS

The various abnormalities detected were recorded and the findings in the two groups were compared.

STATISTICAL ANALYSIS USED

Chi-square test was used to compare between two group proportions.

RESULTS

Thirty out of 4333 (0.69%) candidates in the pre-exposure group and 53 out of 3379 (1.57%) candidates in the post-exposure group showed abnormalities on chest radiographs involving the lung parenchyma, mediastinum, heart, or pleura. In the pre-exposure group, six (0.14%) were found to have underlying cardiac disease and one (0.02%) had tuberculosis. Among the six candidates in the post-exposure group who underwent further investigations in our institute, five (0.15%) were diagnosed to have tuberculosis. Although there was no statistically significant difference in tuberculosis detection between the groups (P = 0.051), there is a trend towards higher detection of tuberculosis in the post-exposure group.

CONCLUSIONS

In a country where the prevalence of tuberculosis is high, the pre-employment chest radiograph may still have a role in detecting tuberculosis in the post-exposure group.

Understanding pretreatment loss to follow-up of tuberculosis patients: an explanatory qualitative study in Chennai, India

Introduction

Pretreatment loss to follow-up (PTLFU)-dropout of patients after diagnosis but before treatment registration-is a major gap in tuberculosis (TB) care in India and globally. Patient and healthcare worker (HCW) perspectives are critical for developing interventions to reduce PTLFU.

Methods

We tracked smear-positive TB patients diagnosed via sputum microscopy from 22 diagnostic centres in Chennai, one of India's largest cities. Patients who did not start therapy within 14 days, or who died or were lost to follow-up before official treatment registration, were classified as PTLFU cases. We conducted qualitative interviews with trackable patients, or family members of patients who had died. We conducted focus group discussions (FGDs) with HCWs involved in TB care. Interview and FGD transcripts were coded and analysed with Dedoose software to identify key themes. We created categories into which themes clustered and identified relationships among thematic categories to develop an explanatory model for PTLFU.

Results

We conducted six FGDs comprising 53 HCWs and 33 individual patient or family member interviews. Themes clustered into five categories. Examining relationships among categories revealed two pathways leading to PTLFU as part of an explanatory model. In the first pathway, administrative and organisational health system barriers-including the complexity of navigating the system, healthcare worker absenteeism and infrastructure failures-resulted in patients feeling frustration or resignation, leading to disengagement from care. In turn, HCWs faced work constraints that contributed to many of these health system barriers for patients. In the second pathway, negative HCW attitudes and behaviours contributed to patients distrusting the health system, resulting in refusal of care.

Conclusion

Health system barriers contribute to PTLFU directly and by amplifying patient-related challenges to engaging in care. Interventions should focus on removing administrative hurdles patients face in the health system, improving quality of the HCW-patient interaction and alleviating constraints preventing HCWs from providing patient-centred care.

Association of Tuberculosis With Household Catastrophic Expenditure in South India

IMPORTANCE

The high household costs associated with tuberculosis (TB) diagnosis and treatment can create barriers to access and adherence, highlighting the urgency of achieving the World Health Organization's End TB Strategy target that no TB-affected households should face catastrophic costs by 2020.

OBJECTIVE

To estimate the occurrence of catastrophic costs associated with TB diagnosis and treatment and to identify socioeconomic indicators associated with catastrophic costs in a setting where TB control strategies have been implemented effectively.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, 455 patients with TB in the Chennai metropolitan area of South India who were treated under the TB control program between February 2017 and March 2018 were interviewed. Patients were interviewed by trained field investigators at 3 time points: at the initiation of treatment, at the end of the intensive phase of treatment, and at the end of the continuation phase of treatment. A precoded interview schedule was used to collect information on demographic, socioeconomic, and clinical characteristics and direct medical, direct nonmedical, and indirect costs. Data analysis was performed from August 2018 to November 2019.

MAIN OUTCOMES AND MEASURES

Direct, indirect, and total costs to patients with TB. Catastrophic costs associated with TB were defined as costs exceeding 20% of the household's annual income. A binary response model was used to determine the factors that were significantly associated with catastrophic costs.

RESULTS

Of 455 patients with TB interviewed, 205 (53%) were aged 19 to 45 years (mean [SD] age, 38.4 [16.0] years), 128 (33%) were female, 72 (19%) were illiterate, 126 (33%) were employed, and 186 (48%) had a single earning member in the family (percentages are based on the 384 patients who were interviewed through the end of the continuation phase of treatment). Sixty-one percent of patients (234 patients) had pulmonary smear positive TB. The proportion of patients with catastrophic costs was 31%. Indirect costs contributed more toward catastrophic cost than did direct costs. Multivariate logistic regression analysis found that unemployment (adjusted odds ratio, 0.2; 95% CI, 0.1-0.5; P < .001) and higher annual household income (Rs 1-200 000, adjusted odds ratio, 0.4; 95% CI, 0.2-0.7; P = .004; Rs >200 000, adjusted odds ratio, 0.2; 95% CI, 0.1-0.5; P < .001) were associated with a decreased likelihood of experiencing catastrophic costs.

CONCLUSIONS AND RELEVANCE

Despite the implementation of free diagnostic and treatment services under a national TB control program, TB-affected households had a high risk of catastrophic costs and further impoverishment. There is an urgent demand to provide additional financial protection for patients with TB.

Strategies for ending tuberculosis in the South-East Asian Region: A modelling approach

Background & objectives:

To support recent political commitments to end tuberculosis (TB) in the World Health Organization South-East Asian Region (SEAR), there is a need to understand by what measures, and with what investment, these goals could be reached. These questions were addressed by using mathematical models of TB transmission by doing the analysis on a country-by-country basis in SEAR.

Methods:

A dynamical model of TB transmission was developed, in consultation with each of the 11 countries in the SEAR. Three intervention scenarios were examined: (i) strengthening basic TB services (including private sector engagement), (ii) accelerating TB case-finding and notification, and (iii) deployment of a prognostic biomarker test by 2025, to guide mass preventive therapy of latent TB infection. Each scenario was built on the preceding ones, in successive combination.

Results:

Comprehensive improvements in basic TB services by 2020, in combination with accelerated case-finding to increase TB detection by at least two-fold by 2020, could lead to a reduction in TB incidence rates in SEAR by 67.3 per cent [95% credible intervals (CrI) 65.3-69.8] and TB deaths by 80.9 per cent (95% CrI 77.9-84.7) in 2035, relative to 2015. These interventions alone would require an additional investment of at least US$ 25 billion. However, their combined effect is insufficient to reach the end TB targets of 80 per cent by 2030 and 90 per cent by 2035. Model projections show how additionally, deployment of a biomarker test by 2025 could end TB in the region by 2035. Targeting specific risk groups, such as slum dwellers, could mitigate the coverage needed in the general population, to end TB in the Region.

Interpretation & conclusions:

While the scale-up of currently available strategies may play an important role in averting TB cases and deaths in the Region, there will ultimately be a need for novel, mass preventive measures, to meet the end TB goals. Achieving these impacts will require a substantial escalation in funding for TB control in the Region.

Impact of incarceration on tuberculosis incidence and its interaction with income distribution inequality in Brazil

BACKGROUND

Deteriorated conditions in the non-prison population can lead to an approximation of its tuberculosis (TB) risk to that in the prison population. We evaluated the association between incarceration and TB incidence rate and its interaction with population income distribution inequality in Brazilian municipalities (2013-2015).

METHODS

We included 954 municipalities with at least one prison. Interaction between the Gini coefficient and prison exposure was analysed in a multiple regression model. We estimated the fraction of TB in the population attributable fraction (PAF) to exposure to prisons according the Gini coefficient.

RESULTS

Compared with the non-prison population, the prisoners had 22.07 times (95% confidence interval [CI] 20.38 to 23.89) the risk of TB in municipalities where the Gini coefficient was <0.60 and 14.96 times (95% CI 11.00 to 18.92) the risk where the Gini coefficient was ≥0.60. A negative interaction in the multiplicative scale was explained by a higher TB incidence in the non-prison population in municipalities with a Gini coefficient ≥0.60. The PAF ranged from 50.06% to 5.19% in municipalities with Gini coefficients <0.40 and ≥0.60, respectively.

CONCLUSIONS

Interventions to reduce prison exposure would have an ostensible impact in population TB incidence rates mainly in settings with lower Gini coefficients. In those with extreme inequality in income distribution, strategies focused on mitigating the effects of socio-economic factors should also be prioritized.

Prevalence of pulmonary tuberculosis in India: A systematic review and meta-analysis

The Revised National Tuberculosis Control Program was started in India in 1997. There has been no nationwide survey to assess the prevalence of pulmonary tuberculosis. We aimed to conduct a systematic review and meta-analysis of published literature to provide an estimate of the prevalence of pulmonary tuberculosis in India. Several databases including Medline, Embase, Scopus, the Cochrane Library, Web of Science, and Google Scholar were searched for studies published between January 1, 1997, and December 31, 2018, which reported the prevalence of pulmonary tuberculosis. Community-based cross-sectional studies conducted among population aged 15 years and above were included. Summary estimates were calculated using random effects models. We identified 13 articles with 16 individual studies having screened 961,633 individuals for pulmonary tuberculosis. The pooled prevalence of bacteriologically positive pulmonary tuberculosis was 295.9 (95% confidence interval: 201.1-390.6) per 100,000 population. The prevalence was higher among males than females and in rural areas compared to urban areas. The pooled prevalence of culture-positive pulmonary tuberculosis (277.8/100,000 population) was higher than smear-positive pulmonary tuberculosis (196.6/100,000 population). The pooled prevalence of bacteriologically positive pulmonary tuberculosis in sensitivity analysis was 186.6/100,000 population. In all these estimates, heterogeneity remained high and significant publication bias was observed. The prevalence of pulmonary tuberculosis varied based on sex and distribution of population in rural and urban areas. There is a need of nationwide population-based survey to estimate the burden of tuberculosis to inform control measures and facilitate monitoring and evaluation.

A male adult skeleton from the Han Dynasty in Shaanxi, China (202 BC-220 AD) with bone changes that possibly represent spinal tuberculosis

Bioarchaeological data for tuberculosis (TB) have been published very sporadically in China or the rest of East Asia. To explore the history of TB in this area, 85 skeletons excavated from the Liuwei Cemetery in Shaanxi, China (202 BC-220 AD) were macroscopically examined to record TB related bone changes. These skeletons represented inhabitants of Maolingyi, an urban area that had a high population density during the Han Dynasty (202 BC-220 CE). Seventeen of the 85 skeletons had spines that were well enough preserved to observe evidence of spinal disease. Among them, a male skeleton aged around 30 years (M34-E) manifested multiple lytic lesions in the eleventh thoracic to second lumbar vertebral bodies (T11 to L2). TB was considered a possible diagnosis for the spinal lesions observed, with differential diagnoses of brucellosis and typhoid. The dense population and overcrowding in urban Maolingyi were considered the potential social risk factors for TB found at this site. The findings of this study contribute to limited knowledge about the history of TB in East Asia and suggest a relationship between population density and the spread of TB in Maolingyi at that time. However, the lack of published bioarchaeological data of TB in East Asia hinders understanding the transmission of TB within Asia and its link to the rest of the world. Further intensive review of archaeological skeletons in Asia is urgently needed. 。, 。85, 17, 。, 30、、。, 。, 。、, , 。, 。, 。.

A review of published spoligotype data indicates the diversity of Mycobacterium tuberculosis from India is under-represented in global databases

BACKGROUND

Mycobacterium tuberculosis (MTBC) lineages differ in clinical presentation, virulence, transmission, drug resistance and immunological responses. Despite having the largest burden of tuberculosis (TB) in the world, strains from India are underrepresented in international databases. We reviewed published spoligotype data to determine the distribution and diversity of MTBC lineages in India.

METHODS

A Pubmed/MEDLINE search identified 34 M. tuberculosis spoligotyping studies from India. Spoligotype patterns were extracted and the Spoligotype International Type (SIT) number, sub-lineage and lineage determined. Minimum Spanning Trees were used to determine relationships between patterns.

RESULTS

We identified 1528 spoligotype patterns distributed across 8300 isolates; 6733 isolates belonged to 472 SITs, with 53% of all isolates belonging to 12 SITs with at least 100 isolates each. Lineage 1 and Lineage 3 made up 67% of all isolates, although a lineage could not be assigned for 16% of isolates. Lineage 1 isolates were most common in Southern, Western and Eastern India, and Lineage 3 was most common in Northern and Central India. The RULE, CBN and KBBN lineage prediction algorithms from the TB-lineage tools performed variably, with the correct lineage predicted correctly for only 64% of patterns with known lineage. Using a consensus definition, 64% of the 1359 isolates with unknown lineage were assigned to Lineage 1, and 14% each were assigned to Lineages 3 and 4. With these lineage assignments, 80% of all isolates belonged to either Lineage 1 or Lineage 3.

CONCLUSION

Our findings indicate significant M. tuberculosis diversity in India. The documentation of 1056 orphan and unreported patterns indicate that this diversity is under-represented in global databases.

Trend in magnitude of tuberculosis in Awi Zone, Northwest Ethiopia: a five-year tuberculosis surveillance data analysis

OBJECTIVE

Ethiopia is among the 30 high tuberculosis (TB) burden countries with annual estimated TB incidence of 164/100,000 population and death rate of 28/100,000 population for 2017. We analyzed the trend in magnitude of tuberculosis in Awi Zone from July 08/2011 up to June 27/2016.

RESULTS

Tuberculosis surveillance data (2012 to 2016) was extracted from Awi Zonal Health Department Health Management Information System database and TB program unit and analyzed by Microsoft Excel 2007^®. Epi-Info⁷ software was used for tuberculosis trend analysis using Chi square for trends. A total of 8193 new TB cases were included in the analysis, of which 18.7% were smear positive PTB cases, 28.5% smear negative PTB (PTB-) cases and 52.7% were extra pulmonary TB (EPTB) cases. All form TB prevalence rate was 213/100,000 population in 2012 and significantly decreased to 189 in 2016 (Trend χ² = 11.97; P = 0.00054). Similarly, all form TB incidence rate was 167/100,000 population in 2012 and decreased to 122 in 2016 (Trend χ² = 37.6; P = 0.000). Overall, the magnitude of tuberculosis had decreased over the periods reviewed. The proportion of EPTB is high. We recommend culture and chest X-ray diagnostic services expansion to capture EPTB and PTB- cases.

Effect of malnutrition on radiographic findings and mycobacterial burden in pulmonary tuberculosis

BACKGROUND

The relationship between malnutrition and tuberculosis (TB) severity is understudied. We investigated the effect of malnutrition on radiographic findings and mycobacterial burden.

METHODS

Subjects included newly diagnosed, smear-positive, culture-confirmed, pulmonary TB cases enrolled in the Regional Prospective Observational Research for TB (RePORT) cohort. Multivariate regression models were used to evaluate the relationship at start of treatment between body mass index (BMI) and chest radiograph (CXR) findings of cavitation and percentage of lung affected and mycobacterial growth indicator tube (MGIT) time to positive (TTP). Severe malnutrition was defined as BMI<16 kg/m2, moderate malnutrition as 16-18.4kg/m2, and "normal"/overweight as ≥18.5 kg/m2.

RESULTS

Of 173 TB cases with chest x-ray data, 131 (76%) were male. The median age was 45 years (range 16-82); 42 (24%) had severe malnutrition and 58 (34%) moderate malnutrition. Median percentage of lung affected was 32% (range 0-95), and 132 (76%) had cavitation. Individuals with severe malnutrition had, on average, 11.1% [95% CI: 4.0-13.3] more lung affected, compared to those with normal BMI, controlling for diabetes and cavitation. In multivariable analyses, cases with severe malnutrition had a 4.6-fold [95% CI, 1.5-14.1] increased odds of cavitation compared to those with normal BMI, controlling for smoking. Median MGIT TTP was 194.5 hours. Neither severe (aRR 0.99; 95% CI, 0.9-1.2) nor moderate (aRR 0.97; 95% CI, 0.8-1.1) malnutrition was associated with MGIT TTP.

CONCLUSION

We found that malnutrition was associated with increased extent of disease and cavitation on CXR. These findings may reflect the immunomodulatory effect of malnutrition on pulmonary pathology.

Active tuberculosis case finding in India - The way forward

Community based active case finding (ACF) for tuberculosis (TB) has seen resurrection in the current armamentarium of many TB managers in their fight toward eliminating TB. This article explores the accuracy and approximate cost of various ACF algorithms currently in vogue in India or those which could be useful, while inputting the sensitivity and specificity of screening and diagnostic tools as estimated from recently conducted community based surveys. This analysis informs that ACF may be prioritized to higher prevalence settings and the diagnostic algorithm for specific setting may be chosen taking into account the expected prevalence, estimated accuracy of the algorithm and resource availability. Further, chest X-ray cannot be used alone as a diagnostic tool and can be relied upon for this purpose when at least one of the three sputum specimen is smear positive. Accuracy of Xpert MTB/RIF as a diagnostic tool in community situations needs to be investigated further. The review brings out significant proportions of initial default and default during treatment among cases detected through ACF thus emphasizing the need for heightened efforts toward preventing the same. The article rounds off emphasizing priority to addressing barriers to speedy scale up of more sensitive diagnostic tools for health center based case finding including in private sector and ACF in high risk clinical groups for early and efficient case detection. It concludes by putting forth certain research areas that would strengthen future efforts.

Modelling the impact of effective private provider engagement on tuberculosis control in urban India

In India, the country with the world’s largest burden of tuberculosis (TB), most patients first seek care in the private healthcare sector, which is fragmented and unregulated. Ongoing initiatives are demonstrating effective approaches for engaging with this sector, and form a central part of India’s recent National Strategic Plan: here we aimed to address their potential impact on TB transmission in urban settings, when taken to scale. We developed a mathematical model of TB transmission dynamics, calibrated to urban populations in Mumbai and Patna, two major cities in India where pilot interventions are currently ongoing. We found that, when taken to sufficient scale to capture 75% of patient-provider interactions, the intervention could reduce incidence by upto 21.3% (95% Bayesian credible interval (CrI) 13.0–32.5%) and 15.8% (95% CrI 7.8–28.2%) in Mumbai and Patna respectively, between 2018 and 2025. There is a stronger impact on TB mortality, with a reduction of up to 38.1% (95% CrI 20.0–55.1%) in the example of Mumbai. The incidence impact of this intervention alone may be limited by the amount of transmission that has already occurred by the time a patient first presents for care: model estimates suggest an initial patient delay of 4–5 months before first seeking care, followed by a diagnostic delay of 1–2 months before ultimately initiating TB treatment. Our results suggest that the transmission impact of such interventions could be maximised by additional measures to encourage early uptake of TB services.

Sub-national TB prevalence surveys in India, 2006-2012: Results of uniformly conducted data analysis

Setting

Community based tuberculosis (TB) prevalence surveys in ten sites across India during 2006–2012

Objective

To re-analyze data of recent sub-national surveys using uniform statistical methods and obtain a pooled national level estimate of prevalence of TB.

Methods

Individuals ≥15 years old were screened by interview for symptoms suggestive of Pulmonary TB (PTB) and history of anti-TB treatment; additional screening by chest radiography was undertaken in five sites. Two sputum specimens were examined by smear and culture among Screen-positives. Prevalence in each site was estimated after imputing missing values to correct for bias introduced by incompleteness of data. In five sites, prevalence was corrected for non-screening by radiography. Pooled prevalence of bacteriologically positive PTB was estimated using Random Effects Model after excluding data from one site. Overall prevalence of TB (all ages, all types) was estimated by adjusting for extra-pulmonary TB and Pediatric TB.

Results

Of 769290 individuals registered, 715989 were screened by interview and 294532 also by radiography. Sputum specimen were examined from 50 852 individuals. Estimated prevalence of smear positive, culture positive and bacteriologically positive PTB varied between 108.4–428.1, 147.9–429.8 and 170.8–528.4 per 100000 populations in different sites. Pooled estimate of prevalence of bacteriologically positive PTB was 350.0 (260.7, 439.0). Overall prevalence of TB was estimated at 300.7 (223.7–377.5) in 2009, the mid-year of surveys. Prevalence was significantly higher in rural compared to urban areas.

Conclusion

TB burden continues to be high in India suggesting further strengthening of TB control activities.