World TB Day 2014: finding the missing 3 million

Cumulative Signaling Through NOD-2 and TLR-4 Eliminates the Mycobacterium Tuberculosis Concealed Inside the Mesenchymal Stem Cells

For a long time, tuberculosis (TB) has been inflicting mankind with the highest morbidity and mortality. Although the current treatment is extremely potent, a few bacilli can still hide inside the host mesenchymal stem cells (MSC). The functional capabilities of MSCs are known to be modulated by TLRs, NOD-2, and RIG-1 signaling. Therefore, we hypothesize that modulating the MSC activity through TLR-4 and NOD-2 can be an attractive immunotherapeutic strategy to eliminate the Mtb hiding inside these cells. In our current study, we observed that MSC stimulated through TLR-4 and NOD-2 (N2.T4) i) activated MSC and augmented the secretion of pro-inflammatory cytokines; ii) co-localized Mtb in the lysosomes; iii) induced autophagy; iv) enhanced NF-κB activity via p38 MAPK signaling pathway; and v) significantly reduced the intracellular survival of Mtb in the MSC. Overall, the results suggest that the triggering through N2.T4 can be a future method of immunotherapy to eliminate the Mtb concealed inside the MSC.

Time for the ethical management of COVID-19 vaccines

The ethical distribution of life-saving medical and public health interventions to vulnerable groups has often been overlooked. Valuation of life linked to an individual's country of origin, the pharmaceutical industry's prioritisation of profit, the exploitation of vulnerable groups in clinical trials, and the resulting hesitancy towards drugs and vaccines have, among other factors, made the human right to health unattainable for many people. The COVID-19 pandemic presents itself as an opportunity to reverse this long-standing trajectory of unethical practices in global health. By ensuring the ethical inclusion of vulnerable groups in the vaccine development process and making a safe, effective vaccine accessible to all, pharmaceutical companies, governments, and international organisations can usher in a new era of global health that relies solely on ethical decision making.

The impact of chest radiography and Xpert MTB/RIF testing among household contacts in Chennai, India

Tuberculosis prevalence surveys have demonstrated the benefit of screening with chest x-ray (CXR) and sensitive diagnostic tests compared to symptoms and smear microscopy. However, in programmatic practice there is little evidence on the yield of different algorithms. We implemented contact tracing in Chennai, India for adult sputum-positive TB patients registered from January 2015 to March 2016. Patients with symptoms or abnormal X-ray findings further underwent testing using Xpert MTB/RIF (Xpert) and smear microscopy. A retrospective cohort study was done to summarize the key findings. We verbally screened 5553 contacts for symptoms, CXR through private sector collaboration, Xpert, and smear microscopy. Overall, 1312 (23.6%) contacts screened positive. CXR alone identified 531 (40.5%) of them, 679 (51.8%) were symptom-positive only, while 102 (7.8%) were positive on both the symptom and CXR screen. Overall, 35 bacteriologically positive cases were identified (0.7%). A standard approach of symptoms screening followed by microscopy identified only 9 (25.7%) of the total number of bacteriologically positive cases, whereas the combination of a CRX screening followed by microscopy identified 13 (37.1%) of the cases. The algorithm of symptoms screening followed by Xpert testing, detected 20 cases, whereas the combination of symptoms and CXR followed by Xpert increased this number to 35 (75% increase compared to symptoms and Xpert). Optimal use of more sensitive screening tests, better diagnostic tests, and novel private sector engagement can improve diagnostic yield in a programmatic setting.

Retrospective Analysis of 28 Cases of Tuberculosis in Pregnant Women in China

While tuberculosis (TB) in pregnant women is reported globally, clinical data is unavailable in China. To describe clinical features and identify difficulties in the diagnosis of pregnancy-related TB, we performed a retrospective study of 28 TB inpatients at Beijing Chest Hospital. The results were presented in terms of interquartile range (IQR) for age, and medians and percentages with respect to the categorical variables. One patient (3.6%) was immediately diagnosed; for 27 patients (96.4%), the median interval from the initial onset of symptoms to diagnosis was five weeks. Eight cases (28.6%) were microbiologically confirmed. 22 (78.6%) were pulmonary TB (PTB), while six (21.4%) were extrapulmonary TB (EPTB). In addition, eight (28.6%) were miliary TB and six (21.4%) were cerebral TB. 27 (96.4%) were cured and one (3.6%) died. 15 neonates were identified, nine of which were healthy. Two were small for the gestational age (SGA) and one was a stillbirth. Three had neonatal TB, one of which died. Nine were legal abortions and four were spontaneous abortions. Indeed, there was a substantial delay in the diagnosis of TB in the pregnant women and a high incidence of both miliary and cerebral TB was evident. With timely treatment, prognosis is positive.

Muscular Tuberculosis: A New Case and a Review of the Literature

Objective: To investigate the clinical manifestations, underlying diseases, pathological features, and therapeutic responses in patients with muscular tuberculosis (MT), which is rare and often misdiagnosed in clinical practice.

Methods: This study describes a rare MT case that was recently diagnosed in our department. Additionally, 18 other MT cases retrieved from the PubMed database from 2,000 to date are included in this study. The clinical manifestations, areas of residence, underlying diseases, laboratory test results, pathology results, and outcomes of the patients were recorded and analyzed.

Results: The MT patients in this study included 13 males and six females with an average age of 34.58 years old. Eight patients were from Asia, and six patients were from Africa, accounting for the majority of patients, at 73.68%. Underlying diseases included flu-like illness in one patient; chronic kidney disease (CKD) in one patient; Sjögren's syndrome in one patient; systemic lupus erythematosus (SLE), lupus nephropathy, and deep vein thrombosis in one patient; and Alzheimer's disease (AD) and Paget's disease in one patient. Two patients had a previous history of tuberculosis, and two patients had contact with suspected tuberculosis patients. All patients presented chronic occult onset, with an average of 3 (1.75, 5) months. Six cases had local masses, and 13 cases had swelling as the main clinical manifestations. Twelve patients (63.2%) presented manifestations at single sites, and seven patients presented manifestations at multiple sites, including the thigh, calf, arm, chest wall, dorsal, psoas, gluteal, and forehead muscles. Of the 19 total patients, 13 (68.4%) reported pain, and only 8 (42.1%) patients presented tuberculosis symptoms. All patients received laboratory results associated with Mycobacterium tuberculosis infection. Fourteen (73.7%) of the 19 patients underwent skeletal muscle biopsy, where granulomatous inflammation was observed. Eighteen patients were treated with anti-tuberculosis therapies. Sixteen patients improved or recovered after anti-tuberculosis treatment, and unfortunately, two patients died.

Conclusion: As a kind of systemic disease, MT is mainly characterized by painful or painless muscle masses and swelling at a single site or at multiple sites. Patients with a history of tuberculosis and immune system disease are susceptible to MT. A diagnosis is mainly made on the basis of the results of pathological biopsy and bacteriological culture. Early diagnosis and timely standardized anti-tuberculosis treatment can improve the prognosis.

Tuberculosis treatment in the private healthcare sector in India: an analysis of recent trends and volumes using drug sales data

BACKGROUND

There is a pressing need for systematic approaches for monitoring how much TB treatment is ongoing in the private sector in India: both to cast light on the true scale of the problem, and to help monitor the progress of interventions currently being planned to address this problem.

METHODS

We used commercially available data on the sales of rifampicin-containing drugs in the private sector, adjusted for data coverage and indication of use. We examined temporal, statewise trends in volumes (patient-months) of TB treatment from 2013 to 2016. We additionally analysed the proportion of drugs that were sold in combination packaging (designed to simplify TB treatment), or as loose pills.

RESULTS

Drug sales suggest a steady trend of TB treatment dispensed by the private sector, from 18.4 million patient-months (95% CI 17.3-20.5) in 2013 to 16.8 patient-months (95% CI 15.5-19.0) in 2016. Overall, seven of 29 states in India accounted for more than 70% of national-level TB treatment volumes, including Uttar Pradesh, Maharashtra and Bihar. The overwhelming majority of TB treatment was dispensed not as loose pills, but in combination packaging with other TB drugs, accounting for over 96% of private sector TB treatment in 2017.

CONCLUSIONS

Our findings suggest consistent levels of TB treatment in the private sector over the past 4 years, while highlighting specific states that should be prioritized for intervention. Drug sales data can be helpful for monitoring a system as large, disorganised and opaque as India's private sector.

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.

Management of tuberculosis by healthcare practitioners in Pakistan: A systematic review

OBJECTIVE

To assess the quality of tuberculosis (TB) care in Pakistan, through determining comparison of healthcare practitioners' knowledge and practices to national and international TB care guidelines.

METHODS

Studies reporting on knowledge, attitudes and practices of public and private practitioners with TB patients were selected through searching electronic databases and grey literature.

FINDINGS

Of 1458 reports, 20 full-texts were assessed, of which 11 met the eligibility and quality criteria; all studies focused on private sector care. Heterogeneity precluded meta-analysis. In 3 of 4 studies, over 50% of practitioners correctly identified a cough as the main TB symptom. However, 4 out of 6 studies showed practitioners' compliance to be low (under 50%) for the use of sputum microscopy in diagnosis. The poorest quality care occurred in the later stages of treatment, with low compliance in prescribing practices for continuation-phase care and in monitoring and recording treatment progress, the latter of which is particularly critical for treatment success.

CONCLUSION

TB care was variable and generally inadequate, with both a lack of knowledge and a small 'know-do' gap evident-practitioners did not use methods that they know they should use. A lack of recent evidence found suggests that the quality of current practices may not be fully captured and further research is needed, especially on non-allopathic, rural and public-sector contexts. Improved training of practitioners, greater availability of recommended diagnostic tools and expansion of public-private partnerships are suggestions for improving the quality of TB care in Pakistan.

Estimating tuberculosis incidence from primary survey data: a mathematical modeling approach

BACKGROUND:

There is an urgent need for improved estimations of the burden of tuberculosis (TB).

OBJECTIVE:

To develop a new quantitative method based on mathematical modelling, and to demonstrate its application to TB in India.

DESIGN:

We developed a simple model of TB transmission dynamics to estimate the annual incidence of TB disease from the annual risk of tuberculous infection and prevalence of smear-positive TB. We first compared model estimates for annual infections per smear-positive TB case using previous empirical estimates from China, Korea and the Philippines. We then applied the model to estimate TB incidence in India, stratified by urban and rural settings.

RESULTS:

Study model estimates show agreement with previous empirical estimates. Applied to India, the model suggests an annual incidence of smear-positive TB of 89.8 per 100 000 population (95%CI 56.8–156.3). Results show differences in urban and rural TB: while an urban TB case infects more individuals per year, a rural TB case remains infectious for appreciably longer, suggesting the need for interventions tailored to these different settings.

CONCLUSIONS:

Simple models of TB transmission, in conjunction with necessary data, can offer approaches to burden estimation that complement those currently being used.

Mesenchymal stem cells internalize Mycobacterium tuberculosis through scavenger receptors and restrict bacterial growth through autophagy

Human mesenchymal stem cells (MSCs) express scavenger receptors that internalize lipids, including oxidized low-density lipoprotein (oxLDL). We report that MSCs phagocytose Mycobacterium tuberculosis (Mtb) through two types of scavenger receptors (SRs; MARCO and SR-B1), as blockade of the receptors with antibodies or siRNA knockdown decreased the uptake of Mtb. MSCs also expressed mannose receptor (MR) that was found to endocytose rhodamine-labeled mannosylated BSA (rMBSA), though the receptor was not involved in the uptake of Mtb. Dil-oxLDL and rMBSA taken up into MSC endosomes colocalized with Mtb phagosomes, thus suggesting that the latter were fusion competent. Phagocytosed Mtb did not replicate within MSCs, thus suggesting an intrinsic control of bacterial growth. Indeed, MSCs exhibited intrinsic autophagy, which was up-regulated after activation with rapamycin. SiRNA knockdown of autophagy initiator beclin-1 enhanced Mtb survival, whereas rapamycin-induced autophagy increased intracellular killing of Mtb. In addition, MSCs secreted nitric oxide after Mtb infection, and inhibition of NO by N(G)-monomethyl-L-arginine enhanced intracellular survival of Mtb. MSCs can be grown in large numbers in vitro, and autologous MSCs transfused into tuberculosis patients have been found to be safe and improve lung immunity. Thus, MSCs are novel phagocytic cells with a potential for immunotherapy in treating multidrug-resistant tuberculosis.

Analysis of host-pathogen modulators of autophagy during Mycobacterium Tuberculosis infection and therapeutic repercussions

Mycobacterium tuberculosis is one of the most deadly human pathogens known today in modern world, responsible for about 1.5 million deaths annually. Development of TB disease occurs only in 1 out of 10 individuals exposed to the pathogen which indicates that the competent host defense mechanisms exist in majority of the hosts to control the infection. In the last decade, autophagy has emerged as a key host immune defense mechanism against intracellular M. tuberculosis infection. Autophagy has been demonstrated not only as an effective antimicrobial mechanism for the clearance of M. tuberculosis, but the process has also been suggested to prevent excessive inflammation to avoid the adverse effects of infection on host. Nevertheless, increasing evidences also show that in order to enhance its intracellular survival, M. tuberculosis has also evolved multiple strategies to compromise the optimal functioning of host autophagic machinery. This review describes an overview of the various host signaling pathways such as pattern recognition receptors, cytokines, nutrient starvation and other cellular stress that have been implicated in induction of autophagy during M. tuberculosis infection. The review also chalk out the complex interplay of several bacterial factors of M. tuberculosis that are known to be involved in compromising autophagy mediated defense of the host. A comprehensive understanding of the interaction of bacterial and host factors at the intersections of autophagic pathways could provide integrative insights for the development of autophagy-based prophylactics and novel therapeutic interventions for TB.

Improving active case finding for tuberculosis in South Africa: informing innovative implementation approaches in the context of the Kharitode trial through formative research

Background

Tuberculosis (TB) is the leading infectious killer worldwide, with approximately 1.8 million deaths in 2015. While effective treatment exists, implementation of active case finding (ACF) methods to identify persons with active TB in a timely and cost-effective manner continues to be a major challenge in resource-constrained settings. Limited qualitative work has been conducted to gain an in-depth understanding of implementation barriers.

Methods

Qualitative research was conducted to inform the development of three ACF strategies for TB to be evaluated as part of the Kharitode cluster-randomised trial being conducted in a rural province of South Africa. This included 25 semi-structured in-depth interviews among 8 TB patients, 7 of their household members and 10 clinic health workers, as well as 4 focus group discussions (2 rural and 2 main town locations) with 6–8 participants each (n = 27). Interviews and focus group discussions explored the context, advantages and limitations, as well as the implications of three ACF methods. Content analysis was utilised to document salient themes regarding their feasibility, acceptability and potential effectiveness.

Results

Study participants (TB patients and community members) reported difficulty identifying TB symptoms and seeking care in a timely fashion. In turn, all stakeholder groups felt that more proactive case finding strategies would be beneficial. Clinic-based strategies (including screening all patients regardless of visit purpose) were seen as the most acceptable method based on participants’ preference ranking of the ACF strategies. However, given the resource constraints experienced by the public healthcare system in South Africa, many participants doubted whether it would be the most effective strategy. Household outreach and incentive-based strategies were described as promising, but participants reported some concerns (e.g. stigma in case of household-based and ethical concerns in the case of incentives). Participants offered insights into how to optimise each strategy, tailoring implementation to community needs (low TB knowledge) and realities (financial constraints, transport, time off from work).

Conclusions

Findings suggest different methods of TB ACF are likely to engage different populations, highlighting the utility of a comprehensive approach.

Trial registration

Clinicaltrials.gov (NCT02808507). Registered June 1, 2016. The participants in this formative study are not trial participants.

R&D in Vaccines Targeting Neglected Diseases: An Exploratory Case Study Considering Funding for Preventive Tuberculosis Vaccine Development from 2007 to 2014

Based on an exploratory case study regarding the types of institutions funding the research and development to obtain new tuberculosis vaccines, this article intends to provoke discussion regarding the provision of new vaccines targeting neglected disease. Although our findings and discussion are mainly relevant to the case presented here, some aspects are more generally applicable, especially regarding the dynamics of development in vaccines to prevent neglected diseases. Taking into account the dynamics of innovation currently seen at work in the vaccine sector, a highly concentrated market dominated by few multinational pharmaceutical companies, we feel that global PDP models can play an important role throughout the vaccine development cycle. In addition, the authors call attention to issues surrounding the coordination of actors and resources in the research, development, manufacturing, and distribution processes of vaccine products arising from PDP involvement.

Cost-effectiveness of triage testing for facility-based systematic screening of tuberculosis among Ugandan adults

BACKGROUND

Systematic screening is often proposed as a way to improve case finding for tuberculosis (TB), but the cost-effectiveness of specific strategies for systematic screening remains poorly studied.

METHODS

We constructed a Markov-based decision analytic model to analyse the cost-effectiveness of triage testing for TB in Uganda, compared against passive case detection with Xpert MTB/RIF. We assumed a triage algorithm whereby all adults presenting to healthcare centres would be screened for cough, and those with cough of at least 2 weeks would receive the triage test, with positive triage results confirmed by Xpert MTB/RIF. We adopted the perspective of the TB control sector, using a primary outcome of the cost per year of life gained (YLG) over a lifetime time horizon.

RESULTS

Systematic screening in a population with a 5% underlying prevalence of TB was estimated to cost US$610 per YLG (95% uncertainty range US$200-US$1859) with chest X-ray (CXR) (US$5 per test, specificity 0.67), or US$588 (US$221-US$1746) with C reactive protein (CRP) (US$3 per test, specificity 0.59). In addition to the cost and specificity of the triage test, cost-effectiveness was most sensitive to the underlying prevalence of TB, monthly risk of mortality in people with untreated TB and the proportion of patients with TB who would be treated in the absence of systematic screening.

CONCLUSIONS

To optimise the cost-effectiveness of facility-based systematic screening of TB with a triage test, it must be carried out in a high-risk population, or use triage tests that are cheaper or more specific than CXR or CRP.

The number of privately treated tuberculosis cases in India: an estimation from drug sales data

Background

Understanding the amount of tuberculosis managed by the private sector in India is crucial to understanding the true burden of the disease in the country, and thus globally. In the absence of quality surveillance data on privately treated patients, commercial drug sales data offer an empirical foundation for disease burden estimation.

Methods

We used a large, nationally representative commercial dataset on sales of 189 anti-tuberculosis products available in India to calculate the amount of anti-tuberculosis treatment in the private sector in 2013–14. We corrected estimates using validation studies that audited prescriptions against tuberculosis diagnosis, and estimated uncertainty using Monte Carlo simulation. To address implications for numbers of patients with tuberculosis, we explored varying assumptions for average duration of tuberculosis treatment and accuracy of private diagnosis.

Findings

There were 17·793 million patient-months (95% credible interval 16·709 million to 19·841 million) of anti-tuberculosis treatment in the private sector in 2014, twice as many as the public sector. If 40–60% of private-sector tuberculosis diagnoses are correct, and if private-sector tuberculosis treatment lasts on average 2–6 months, this implies that 1·19–5·34 million tuberculosis cases were treated in the private sector in 2014 alone. The midpoint of these ranges yields an estimate of 2·2 million cases, two to three times higher than currently assumed.

Interpretation

India's private sector is treating an enormous number of patients for tuberculosis, appreciably higher than has been previously recognised. Accordingly, there is a re-doubled need to address this burden and to strengthen surveillance. Tuberculosis burden estimates in India and worldwide require revision.

Funding

Bill & Melinda Gates Foundation.

Tuberculosis 2015: Burden, Challenges and Strategy for Control and Elimination

Tuberculosis (TB) is a leading cause of morbidity and mortality worldwide, accounting for about 9.6 million new cases and 1.5 million deaths annually. The poorest and socially excluded groups carry the largest burden of disease, which makes it essential to properly address the social determinants of health through poverty reduction measures and targeted interventions on high-risk populations. The spread of multidrug-resistance TB requires special attention and highlights the need to foster research on TB diagnostics, new drugs and vaccines. Although many advances have been made in the fight against TB over the last twenty years, a lot is still needed to achieve global elimination. The new end-TB strategy that was first launched in 2014 by the World Health Organization, is fully in line with the seventeen Sustainable Development Goals that came into effect since January 2016 and sets ambitious goals for the post-2015 agenda. A 90% reduction in TB-related mortality and an 80% decline in TB incidence within 2030 as well as the abolition of catastrophic expenditures for TB-affected people are the main targets of this strategy. Strong government commitment and adequate financing from all countries together with community engagement and appropriate investments in research are necessary in order to reach these objectives.

Mycobacterial Protein Tyrosine Phosphatases A and B Inhibitors Augment the Bactericidal Activity of the Standard Anti-tuberculosis Regimen

Novel drugs are required to shorten the duration of treatment for tuberculosis (TB) and to combat the emergence of drug resistance. One approach has been to identify and target Mycobacterium tuberculosis (Mtb) virulence factors, which promote the establishment of TB infection and pathogenesis. Mtb produces a number of virulence factors, including two protein tyrosine phosphatases (PTPs), mPTPA and mPTPB, to evade the antimicrobial functions of host macrophages. To assess the therapeutic potential of targeting the virulent Mtb PTPs, we developed highly potent and selective inhibitors of mPTPA (L335-M34) and mPTPB (L01-Z08) with drug-like properties. We tested the bactericidal activity of L335-M34 and L01-Z08 alone or together in combination with the standard antitubercular regimen of isoniazid-rifampicin-pyrazinamide (HRZ) in the guinea pig model of chronic TB infection, which faithfully recapitulates some of the key histological features of human TB lesions. Following a single dose of L335-M34 50mg/kg and L01-Z08 20 mg/kg, plasma levels were maintained at levels 10-fold greater than the biochemical IC₅₀ for 12-24 hours. Although neither PTP inhibitor alone significantly enhanced the antibacterial activity of HRZ, dual inhibition of mPTPA and mPTPB in combination with HRZ showed modest synergy, even after 2 weeks of treatment. After 6 weeks of treatment, the degree of lung inflammation correlated with the bactericidal activity of each drug regimen. This study highlights the potential utility of targeting Mtb virulence factors, and specifically the Mtb PTPs, as a strategy for enhancing the activity of standard anti-TB treatment.

Taking forward the World TB Day 2016 theme 'Unite to End Tuberculosis' for the WHO Africa Region

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Tuberculosis (TB) has remained a global emergency ever since it was declared as such by the World Health Organization (WHO) in 1993.

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Of the 9.6 million people who developed TB in 2014, 28% were in the WHO Africa Region, where the case rate was 281 per 100 000 population.

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An estimated 1.2 million (12%) TB cases were HIV-positive and the Africa Region accounted for 74% of these cases.

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The global spread of multidrug-resistant TB (MDR-TB) is now a major public health challenge.

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Scientific, political, and funder communities seriously need to ‘Unite to End TB’, the theme of the 2016 World TB Day.

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TB control programs in Africa can only succeed if mechanisms for close engagement of developing country scientists, healthcare workers, patient groups, governments, and policy-makers are ensured by funding and donor agencies.

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Several funder, political, and community initiatives provide hope for achieving the goals of the WHO post-2015 TB strategy.

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TB activities and funder investments in Africa need to be aligned in parallel with international efforts at improving social and living conditions and with the ‘one health’ initiative.

Tuberculosis (TB) remains a global emergency, with an estimated 9.6 million new TB cases worldwide reported in 2014. Twenty-eight percent of these cases were in the World Health Organization (WHO) Africa Region, where the annual case detection rate was 281 per 100 000 population—more than double the global average of 133 per 100 000. Of the 9.6 million people who developed TB, an estimated 1.2 million (12%) were HIV-positive, and the Africa Region accounted for 74% of these cases. Three million people with TB remain undiagnosed and untreated. Globally, an estimated 480 000 had multidrug-resistant TB (MDR-TB). Whilst of the African countries, only South Africa has reported a high prevalence of MDR-TB, it is likely that all of Sub-Saharan Africa has an unreported high load of drug-resistant TB. Tragically, in 2014, only 48% of individuals diagnosed with MDR-TB had successful treatment and an estimated 190 000 people died of MDR-TB. Of the global TB funding gap of US$ 0.8 billion, the largest funding gap was in the Africa Region, amounting to US$ 0.4 billion in 2015. The MDR-TB pandemic in particular now threatens to devastate entire regions and may fundamentally alter the life-expectancy and demographic profile of many countries in Sub-Saharan Africa. The theme designated for this year's World TB Day, March 24, 2016, is ‘Unite to End TB’. From the Africa Region, there is an urgent need to seriously address the political, economic, and social factors that influence host–Mycobacterium tuberculosis interactions and result in disease. Recent political and funder initiatives that provide renewed hope for the alleviation of Africa's TB and TB/HIV problems are discussed.

Intestinal tuberculosis and Crohn's disease: challenging differential diagnosis

Along with epidemiological changes in tuberculosis (TB) and an increased incidence of Crohn's disease (CD), the differential diagnosis of intestinal TB (ITB) and CD is of vital importance and has become a clinical challenge because treatment based on misdiagnosis may lead to fatal outcomes. In this study, we reviewed the similarities and differences in clinical, endoscopic, radiological and histological features of these two diseases. Concomitant pulmonary TB, ascites, night sweats, involvement of fewer than four segments of the bowel, patulous ileocecal valve, transverse ulcers, scars or pseudopolyps strongly indicate ITB. Bloody stools, perianal signs, chronic diarrhea, extraintestinal manifestations, anorectal lesions, longitudinal ulcers and a cobblestone appearance are all suggestive of CD. Significant differences in the size, number, location and patterns of granulomas in ITB and CD with regard to their histopathologic features have been noted. Immune stain of cell surface markers is also helpful. Interferon-γ release assay and polymerase chain reaction analysis have achieved satisfactory sensitivity and specificity in the diagnosis of ITB. Computed tomography enterographic findings of segmental small bowel or left colon involvement, mural stratification, the comb sign and fibrofatty proliferation are significantly more common in CD, whereas mesenteric lymph node changes (calcification or central necrosis) and focal ileocecal lesions are more frequently seen in ITB. A diagnosis should be carefully established before the initiation of the therapy. In suspicious cases, short-term empirical anti-TB therapy is quite efficient to further confirm the diagnosis.

Tackling the tuberculosis epidemic in sub-Saharan Africa--unique opportunities arising from the second European Developing Countries Clinical Trials Partnership (EDCTP) programme 2015-2024

Tuberculosis (TB) today remains a global emergency affecting 9.0 million people globally. The African Region bears the highest global TB/HIV burden and over 50% of TB cases in SSA are co-infected with HIV. An estimated 1.5 million died from the TB globally in 2013. A large majority of the 360,000 HIV-positive TB cases who died were from sub-Saharan Africa. Research and development is an important pillar of the WHO post-2015 global TB strategy. Advances in development of diagnostics, drugs, host-directed therapies, and vaccines will require evaluation under field conditions through multi-centre clinical trials at different geographical locations. Thus it is critically important that these evaluations are fully supported by all African governments and the capacity, trained staff and infrastructure required to perform the research and evaluations is built and made available. This viewpoint article reviews the opportunities provided by recently launched second programme (2015-2024) of the European & Developing Countries Clinical Trials Partnership (EDCTP2) for tackling the TB epidemic in Africa through its magnanimous portfolio. The unique opportunities provided by EDCTP2 for leadership of scientific research in TB and other diseases fully devolving to Africa are also covered.

Active Tuberculosis in HIV-Exposed Tanzanian Children up to 2 years of Age: Early-Life Nutrition, Multivitamin Supplementation and Other Potential Risk Factors

BACKGROUND

Over half a million children worldwide develop active tuberculosis (TB) each year. Early-life nutritional exposures have rarely been examined in relation to pediatric TB among HIV-exposed children. We therefore investigated independent associations of early-life nutritional exposures with active TB among HIV-exposed children up to 2 years of age.

METHODS

Participants were children from a randomized controlled multivitamin supplementation trial conducted in Dar es Salaam, Tanzania, from August 2004 to May 2008, who received daily multivitamin supplements or placebo for 24 months.

RESULTS

Lower mean corpuscular volumes [relative risks (RR): 0.48, 95% confidence interval (CI): 0.27, 0.87] and higher birth weights (RR: 0.61, 95% CI: 0.37, 0.99) were protective against active TB, whereas multivitamin supplementation was not associated with TB risk (RR: 0.87, 95% CI: 0.65, 1.16).

CONCLUSIONS

Knowledge of nutrition-related risk and protective factors for TB in HIV-exposed children could enhance preventive and case-finding activities in this population, contributing to efforts to reduce the global TB burden.

HIV treatment cascade in tuberculosis patients

PURPOSE OF REVIEW

Globally, the number of deaths associated with tuberculosis (TB) and HIV coinfection remains unacceptably high. We review the evidence around the impact of strengthening the HIV treatment cascade in TB patients and explore recent findings about how best to deliver integrated TB/HIV services.

RECENT FINDINGS

There is clear evidence that the timely provision of antiretroviral therapy (ART) reduces mortality in TB/HIV coinfected adults. Despite this, globally in 2013, only around a third of known HIV-positive TB cases were treated with ART. Although there is some recent evidence exploring the barriers to achieve high coverage of HIV testing and ART initiation in TB patients, our understanding of which factors are most important and how best to address these within different health systems remains incomplete. There are some examples of good practice in the delivery of integrated TB/HIV services to improve the HIV treatment cascade. However, evidence of the impact of such strategies is of relatively low quality for informing integrated TB/HIV programming more broadly. In most settings, there remain barriers to higher-level organizational and functional integration.

SUMMARY

There remains a need for commitment to patient-centred integrated TB/HIV care in countries affected by the dual epidemic. There is a need for better quality evidence around how best to deliver integrated services to strengthen the HIV treatment cascade in TB patients, both at primary healthcare level and within community settings.

Host-Directed Therapies for Tackling Multi-Drug Resistant Tuberculosis: Learning From the Pasteur-Bechamp Debates

Tuberculosis remains a global emergency causing an estimated 1.5 million deaths annually. For several decades the major focus of tuberculosis treatment has been on antibiotic development targeting Mycobacterium tuberculosis. The lengthy tuberculosis treatment duration and poor treatment outcomes associated with multi-drug resistant tuberculosis (MDR-TB) are of major concern. The sparse new tuberculosis drug pipeline and widespread emergence of MDR-TB signal an urgent need for more innovative interventions to improve treatment outcomes. Building on the historical Pasteur-Bechamp debates on the role of the "microbe" vs the "host internal milieu" in disease causation, we make the case for parallel investments into host-directed therapies (HDTs). A range of potential HDTs are now available which require evaluation in randomized controlled clinical trials as adjunct therapies for shortening the duration of tuberculosis therapy and improving treatment outcomes for drug-susceptible tuberculosis and MDR-TB. Funder initiatives that may enable further research into HDTs are described.

Burden of tuberculosis at post mortem in inpatients at a tertiary referral centre in sub-Saharan Africa: a prospective descriptive autopsy study

BACKGROUND

Patients with subclinical tuberculosis, smear-negative tuberculosis, extrapulmonary tuberculosis, multidrug-resistant tuberculosis, and asymptomatic tuberculosis are difficult to diagnose and may be missed at all points of health care. We did an autopsy study to ascertain the burden of tuberculosis at post mortem in medical inpatients at a tertiary care hospital in Lusaka, Zambia.

METHODS

Between April 5, 2012, and May 22, 2013, we did whole-body autopsies on inpatients aged at least 16 years who died in the adult inpatient wards at University Teaching Hospital, Lusaka, Zambia. We did gross pathological and histopathological analysis and processed lung tissues from patients with tuberculosis through the GeneXpert MTB/RIF assay to identify patients with multidrug-resistant tuberculosis. The primary outcome measure was specific disease or diseases stratified by HIV status. Secondary outcomes were missed tuberculosis, multidrug-resistant tuberculosis, and comorbidities with tuberculosis. Data were analysed using Pearson χ(2), the Mann-Whitney U test, and binary logistic regression.

FINDINGS

The median age of the 125 included patients was 35 years (IQR 29-43), 80 (64%) were men, and 101 (81%) were HIV positive. 78 (62%) patients had tuberculosis, of whom 66 (85%) were infected with HIV. 35 (45%) of these 78 patients had extrapulmonary tuberculosis. The risk of extrapulmonary tuberculosis was higher among HIV-infected patients than among uninfected patients (adjusted odds ratio 5·14, 95% CI 1·04-24·5; p=0·045). 20 (26%) of 78 patients with tuberculosis were not diagnosed during their life and 13 (17%) had undiagnosed multidrug-resistant tuberculosis. Common comorbidities with tuberculosis were pyogenic pneumonia in 26 patients (33%) and anaemia in 15 (19%).

INTERPRETATION

Increased clinical awareness and more proactive screening for tuberculosis and multidrug-resistant tuberculosis in inpatient settings is needed. Further autopsy studies are needed to ascertain the generalisability of the findings.

FUNDING

UBS Optimus Foundation, EuropeAID, and European Developing Countries Clinical Trials Partnership (EDCTP).

'Complex' but coping: experience of symptoms of tuberculosis and health care seeking behaviours--a qualitative interview study of urban risk groups, London, UK

BACKGROUND

Tuberculosis awareness, grounded in social cognition models of health care seeking behaviour, relies on the ability of individuals to recognise symptoms, assess their risk and access health care (passive case finding). There is scant published research into the health actions of 'hard-to-reach' groups with tuberculosis, who represent approximately 17% of the London TB caseload. This study aimed to analyse patients' knowledge of tuberculosis, their experiences of symptoms and their health care seeking behaviours.

METHODS

Qualitative interviews were conducted with 17 participants, predominantly homeless and attending a major tuberculosis centre in London, UK. Most had complex medical and social needs including drug and alcohol use or immigration problems affecting entitlement to social welfare. Analytical frameworks aimed to reflect the role of broader social structures in shaping individual health actions.

RESULTS

Although participants demonstrated some knowledge of tuberculosis their awareness of personal risk was low. Symptoms commonly associated with tuberculosis were either not recognised or were attributed to other causes for which participants would not ordinarily seek health care. Many accessed health care by chance and, for some, for health concerns other than tuberculosis.

CONCLUSIONS

Health education, based on increasing awareness of symptoms, may play a limited role in tuberculosis care for populations with complex health and social needs. The findings support the intensification of outreach initiatives to identify groups at risk of tuberculosis and the development of structured care pathways which support people into prompt diagnosis and treatment.