Genome-wide profiling of circulatory microRNAs associated with cognition and dementia.

INTRODUCTION: MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression. Their role in the pathophysiology of dementia and potential as biomarkers remains undetermined. METHODS: We conducted a single- (one-by-one) and multi-marker (joint) analysis to identify well-expressed circulating miRNAs in plasma (total = 591) associated with general cognition and incident dementia, for 1615 participants of the population-based Rotterdam Study. RESULTS: During single-marker analysis, 47 miRNAs were nominally (P ≤ .05) associated with cognition and 18 miRNAs were nominally associated with incident dementia, after adjustment for potential confounders. Three miRNAs were common between cognition and dementia (miR-4539, miR-372-3p, and miR-566), with multi-marker analysis revealing another common miRNA (miR-7106-5p). In silico analysis of these four common miRNAs led to several putative target genes expressed in the brain, highlighting the mitogen-activated protein kinase signaling pathway. DISCUSSION: We provide population-based evidence on the relationship between circulatory miRNAs with cognition and dementia, including four common miRNAs that may elucidate downstream mechanisms. HIGHLIGHTS: MicroRNAs (miRNAs) are involved in the (dys)function of the central nervous system. Four circulating miRNAs in plasma are associated with cognition and incident dementia. Several predicted target genes of these four miRNAs are expressed in the brain. These four miRNAs may be linked to pathways underlying dementia. Although miRNAs are promising biomarkers, experimental validation remains essential.

A guide to aid the selection of diagnostic tests.

In recent years, a wide range of diagnostic tests has become available for use in resource-constrained settings. Accordingly, a huge number of guidelines, performance evaluations and implementation reports have been produced. However, this wealth of information is unstructured and of uneven quality, which has made it difficult for end-users, such as clinics, laboratories and health ministries, to determine which test would be best for improving clinical care and patient outcomes in a specific context. This paper outlines a six-step guide to the selection and implementation of in vitro diagnostic tests based on Médecins Sans Frontières' practical experience: (i) define the test's purpose; (ii) review the market; (iii) ascertain regulatory approval; (iv) determine the test's diagnostic accuracy under ideal conditions; (v) determine the test's diagnostic accuracy in clinical practice; and (vi) monitor the test's performance in routine use. Gaps in the information needed to complete these six steps and gaps in regulatory systems are highlighted. Finally, ways of improving the quality of diagnostic tests are suggested, such as establishing a model list of essential diagnostics, establishing a repository of information on the design of diagnostic studies and improving quality control and postmarketing surveillance.

Depuis quelques années, de multiples tests diagnostiques sont disponibles dans les lieux de soins disposant de ressources limitées. En conséquence, un nombre considérable de directives, d'évaluations des performances et de rapports de mise en œuvre ont été élaborés. Cette masse d'informations manque néanmoins de structure et est de qualité inégale, raisons pour lesquelles les utilisateurs finaux, tels que les centres de santé, les laboratoires et les ministères de la Santé, ont eu des difficultés à déterminer quel test conviendrait le mieux pour améliorer les soins cliniques et l'état de santé des patients dans un contexte donné. Ce document présente un guide en six étapes pour faciliter la sélection et la mise en œuvre de tests diagnostiques in vitro, en s'appuyant sur l'expérience pratique de Médecins Sans Frontières: (i) définir l'objectif du test; (ii) analyser le marché; (iii) obtenir l'approbation réglementaire; (iv) déterminer la précision du test diagnostique dans des conditions idéales; (v) déterminer la précision du test diagnostique dans le cadre d'une pratique clinique; et (vi) suivre les performances du test dans le cadre d'une utilisation courante. Ce document met en avant les informations manquantes nécessaires pour accomplir ces six étapes et les lacunes des systèmes de réglementation. Enfin, il propose des moyens d'améliorer la qualité des tests diagnostiques, à travers l'établissement d'une liste modèle des diagnostics essentiels, l'élaboration d'un référentiel d'informations sur la réalisation des études diagnostiques, et l'amélioration du contrôle de la qualité et de la pharmacovigilance.

En los últimos años se ha desarrollado una amplia variedad de pruebas de diagnóstico para el uso en entornos con recursos limitados. Como consecuencia, se ha producido una gran cantidad de manuales, evaluaciones de rendimiento e informes de implementación. No obstante, esta abundancia de información está desestructurada y tiene una calidad irregular. Esto ha dificultado que los usuarios finales, como clínicas, laboratorios y ministerios de salud, puedan determinar qué prueba es la más indicada para mejorar la atención sanitaria y los resultados de los pacientes en un contexto específico. En el presente informe se describe un manual de seis pasos para la selección y la implementación de pruebas de diagnóstico in vitro sobre la base de la experiencia práctica de Mèdecins Sans Frontières: (i) definir el propósito de la prueba; (ii) revisar el mercado; (iii) verificar la aprobación normativa; (iv) determinar la precisión del diagnóstico de la prueba en condiciones ideales; (v) determinar la precisión del diagnóstico de la prueba en la práctica clínica; y (vi) controlar el rendimiento de la prueba en su uso habitual. Se destacan los vacíos en la información necesarios para completar estos seis pasos y los vacíos del sistema normativo. Finalmente, se sugieren maneras para mejorar la calidad de las pruebas de diagnóstico, como establecer una lista modelo de los diagnósticos esenciales, establecer un repositorio de información sobre el diseño de los estudios de diagnósticos y mejorar el control de calidad y el control del postmarketing.

Provider initiated tuberculosis case finding in outpatient departments of health care facilities in Ghana: yield by screening strategy and target group.

BACKGROUND: Meticulous identification and investigation of patients presenting with tuberculosis (TB) suggestive symptoms rarely happen in crowded outpatient departments (OPDs). Making health providers in OPDs diligently follow screening procedures may help increase TB case detection. From July 2010 to December 2013, two symptom based TB screening approaches of varying cough duration were used to screen and test for TB among general outpatients, PLHIV, diabetics and contacts in Accra, Ghana. METHODS: This study was a retrospective analysis comparing the yield of TB cases using two different screening approaches, allocated to selected public health facilities. In the first approach, the conventional 2 weeks cough duration with or without other TB suggestive symptoms was the criterion to test for TB in attendants of 7 general OPDs. In the second approach the screening criteria cough of >24 hours, as well as a history of at least one of the following symptoms: fever, weight loss and drenching night sweats were used to screen and test for TB among attendants of 3 general OPDs, 7 HIV clinics and 2 diabetes clinics. Contact investigation was initiated for index TB patients. The facilities documented the number of patients verbally screened, with presumptive TB, tested using smear microscopy and those diagnosed with TB in order to calculate the yield and number needed to screen (NNS) to find one TB case. Case notification trends in Accra were compared to those of a control area. RESULTS: In the approach using >24-hour cough, significantly more presumptive TB cases were identified among outpatients (0.82% versus 0.63%), more were tested (90.1% versus 86.7%), but less smear positive patients were identified among those tested (8.0% versus 9.4%). Overall, all forms of TB cases identified per 100,000 screened were significantly higher in the >24-hour cough approach at OPD (92.7 for cough >24 hour versus 82.7 for cough >2 weeks ), and even higher in diabetics (364), among contacts (693) and PLHIV (995). NNS (95% Confidence Interval) varied from 100 (93-109) for PLHIV, 144 (112-202) for contacts, 275 (197-451) for diabetics and 1144 (1101-1190) for OPD attendants. About 80% of the TB cases were detected in general OPDs. Despite the intervention, notifications trends were similar in the intervention and control areas. CONCLUSION: The >24-hour cough approach yielded more TB cases though required TB testing for a larger number of patients. The yield of TB cases per 100,000 population screened was highest among PLHIV, contacts, and diabetics, but the majority of cases were detected in general OPDs. The intervention had no discernible impact on general case notification.

"I don't have options but to persevere." Experiences and practices of care for HIV and diabetes in rural Tanzania: a qualitative study of patients and family caregivers.

BACKGROUND: The high prevalence of chronic diseases in Tanzania is putting a strain on the already stretched health care services, patients and their families. This study sought to find out how health care for diabetes and HIV is perceived, practiced and experienced by patients and family caregivers, to inform strategies to improve continuity of care. METHODS: Thirty two in-depth interviews were conducted among 19 patients (10 HIV, 9 diabetes) and 13 family caregivers (6 HIV, 7 diabetes). Diabetes patients and caregivers were accessed through one referral facility. HIV patients and caregivers were accessed through HIV clinics at the district hospital, one health centre and one dispensary respectively. The innovative care for chronic conditions framework informed the study design. Data was analysed with the help of Nvivo 10. RESULTS: Three major themes emerged; preparedness and practices in care, health care at health facilities and community support in care for HIV and diabetes. In preparedness and practices, HIV patients and caregivers knew more about aspects of HIV than did diabetes patients and caregivers on diabetes aspects. Continued education on care for the conditions was better structured for HIV than diabetes. On care at facilities, HIV and diabetes patients reported that they appreciated familiarity with providers, warm reception, gentle correction of mistakes and privacy during care. HIV services were free of charge at all levels. Costs involved in seeking services resulted in some diabetes patients to not keep appointments. There was limited community support for care of diabetes patients. Community support for HIV care was through community health workers, patient groups, and village leaders. CONCLUSION: Diabetes and HIV have socio-cultural and economic implications for patients and their families. The HIV programme is successfully using decentralization of health services, task shifting and CHWs to address these implications. For diabetes and NCDs, decentralization and task shifting are also important and, strengthening of community involvement is warranted for continuity of care and patient centeredness in care. While considering differences between HIV and diabetes, we have shown that Tanzania's rich experiences in community involvement in health can be leveraged for care and treatment of diabetes and other NCDs.

Optimizing multiplex SNP-based data analysis for genotyping of Mycobacterium tuberculosis isolates.

BACKGROUND: Multiplex ligation-dependent probe amplification (MLPA) is a powerful tool to identify genomic polymorphisms. We have previously developed a single nucleotide polymorphism (SNP) and large sequence polymorphisms (LSP)-based MLPA assay using a read out on a liquid bead array to screen for 47 genetic markers in the Mycobacterium tuberculosis genome. In our assay we obtain information regarding the Mycobacterium tuberculosis lineage and drug resistance simultaneously. Previously we called the presence or absence of a genotypic marker based on a threshold signal level. Here we present a more elaborate data analysis method to standardize and streamline the interpretation of data generated by MLPA. The new data analysis method also identifies intermediate signals in addition to classification of signals as positive and negative. Intermediate calls can be informative with respect to identifying the simultaneous presence of sensitive and resistant alleles or infection with multiple different Mycobacterium tuberculosis strains. RESULTS: To validate our analysis method 100 DNA isolates of Mycobacterium tuberculosis extracted from cultured patient material collected at the National TB Reference Laboratory of the National Center for Tuberculosis and Lung Diseases in Tbilisi, Republic of Georgia were tested by MLPA. The data generated were interpreted blindly and then compared to results obtained by reference methods. MLPA profiles containing intermediate calls are flagged for expert review whereas the majority of profiles, not containing intermediate calls, were called automatically. No intermediate signals were identified in 74/100 isolates and in the remaining 26 isolates at least one genetic marker produced an intermediate signal. CONCLUSION: Based on excellent agreement with the reference methods we conclude that the new data analysis method performed well. The streamlined data processing and standardized data interpretation allows the comparison of the Mycobacterium tuberculosis MLPA results between different experiments. All together this will facilitate the implementation of the MLPA assay in different settings.

Critical review of the Stepwise Laboratory Improvement Process Towards Accreditation (SLIPTA): suggestions for harmonization, implementation and improvement.

OBJECTIVE: Clinical laboratories in low- and middle-income countries (LMIC) need fundamental improvement because quality laboratory services are essential for the decision-making capacity of clinicians, health workers and public health authorities. To this end, a tiered accreditation scheme Stepwise Laboratory Improvement Process Towards Accreditation (SLIPTA) was developed by WHO-AFRO, CDC and others for clinical laboratories in LMIC. One to five stars are accredited to laboratories based on the level of compliance with a checklist. Our aim was to evaluate the quality and applicability of this accreditation scheme compared with international quality standards. METHODS: We performed a critical review of this scheme to formulate recommendations for implementation, harmonization and improvement. Two analyses were performed: one assessing its coverage of the ISO 15189:2007 standard and one to identify and evaluate priorities of the accreditation checklist. RESULTS: Although the content of the checklist covers all aspects of total quality management, it strongly prioritizes resource management activities. We recommend identifying critical requirements for each tier of accreditation to assure a certain level of quality for each tier or instead using a pass/fail approach towards accreditation. In addition, the checklist should include more questions for assessing proper management, ethics and continuous improvement to meet ISO 15189. CONCLUSION: Launching accreditation schemes for laboratories in LMIC should be encouraged. After further optimization of SLIPTA, clinical laboratories may certainly benefit, leading to more correctly diagnosed patients and less waste of resources.

The realistic performance achievable with mycobacterial automated culture systems in high and low prevalence settings.

BACKGROUND: Diagnostic tests are generally used in situations with similar pre-test probability of disease to where they were developed. When these tests are applied in situations with very different pre-test probabilities of disease, it is informative to model the likely implications of known characteristics of test performance in the new situation. This is the case for automated Mycobacterium tuberculosis (MTB) liquid culture systems for tuberculosis case detection which were developed and are widely used in low burden settings but are only beginning to be applied on a large scale in high burden settings. METHODS: Here we model the performance of MTB liquid culture systems in high and low tuberculosis (TB) prevalence settings using detailed published data concentrating on the likely frequency of cross-contamination events. RESULTS: Our model predicts that as the TB prevalence in the suspect population increases there is an exponential increase in the risk of MTB cross-contamination events expected in otherwise negative samples, even with equivalent technical performance of the laboratories. Quality control and strict cross-contamination measures become increasingly critical as the burden of MTB infection among TB suspects increases. Even under optimal conditions the realistically achievable specificity of these systems in high burden settings will likely be significantly below that obtained in low TB burden laboratories. CONCLUSIONS: Liquid culture systems can play a valuable role in TB case detection in laboratories in high burden settings, but laboratory workers, policy makers and clinicians should be aware of the increased risks, independent of laboratory proficiency, of cross-contamination events in high burden settings.

Review of the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) version 2:2015.

BACKGROUND: In 2011 the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) was launched, aimed at strengthening the quality and competence of African clinical, public health and reference laboratories. We reviewed the first version of the SLIPTA checklist in 2011. The continued development and publication of a new version of the International Organization for Standardization (ISO) 15189 standard demands a renewed review. OBJECTIVE: This study aimed to determine the suitability of SLIPTA in guiding laboratories towards ISO 15189:2012 compliance and accreditation and provide recommendations for further SLIPTA improvement. METHODS: The study was conducted between September 2018 and April 2019. Coverage of ISO 15189:2012 by SLIPTA checklist version 2:2015 was determined and the point distribution of the scoring system over the different sections of the SLIPTA checklist was re-investigated. These findings were compared with the review of the first version of the SLIPTA checklist (based on ISO 15189:2007) and with findings published on SLIPTA implementation and roll-out. RESULTS: The coverage of ISO 15189 by the SLIPTA checklist has increased, even though ISO 15189:012 is more extensive than ISO 15189:2007. The point distribution is still skewed towards sections related to quality planning rather than quality control and improvement. Although to date 314 laboratories have been assessed, barriers for laboratories to participate in SLIPTA are high. Sustainability of SLIPTA results is insufficiently studied. CONCLUSION: SLIPTA checklist version 2:2015 has improved compared to earlier versions. We recommend increasing accessibility for laboratories to participate and increasing guidance for ISO-based quality management system implementation.

Multi-Omics Analysis Reveals MicroRNAs Associated With Cardiometabolic Traits.

MicroRNAs (miRNAs) are non-coding RNA molecules that regulate gene expression. Extensive research has explored the role of miRNAs in the risk for type 2 diabetes (T2D) and coronary heart disease (CHD) using single-omics data, but much less by leveraging population-based omics data. Here we aimed to conduct a multi-omics analysis to identify miRNAs associated with cardiometabolic risk factors and diseases. First, we used publicly available summary statistics from large-scale genome-wide association studies to find genetic variants in miRNA-related sequences associated with various cardiometabolic traits, including lipid and obesity-related traits, glycemic indices, blood pressure, and disease prevalence of T2D and CHD. Then, we used DNA methylation and miRNA expression data from participants of the Rotterdam Study to further investigate the link between associated miRNAs and cardiometabolic traits. After correcting for multiple testing, 180 genetic variants annotated to 67 independent miRNAs were associated with the studied traits. Alterations in DNA methylation levels of CpG sites annotated to 38 of these miRNAs were associated with the same trait(s). Moreover, we found that plasma expression levels of 8 of the 67 identified miRNAs were also associated with the same trait. Integrating the results of different omics data showed miR-10b-5p, miR-148a-3p, miR-125b-5p, and miR-100-5p to be strongly linked to lipid traits. Collectively, our multi-omics analysis revealed multiple miRNAs that could be considered as potential biomarkers for early diagnosis and progression of cardiometabolic diseases.

Resistant mutants of Mycobacterium tuberculosis selected in vitro do not reflect the in vivo mechanism of isoniazid resistance.

OBJECTIVES: The high prevalence of isoniazid-resistant Mycobacterium tuberculosis is often explained by a high mutation rate for this trait, although detailed information to support this theory is absent. We studied the development of isoniazid resistance in vitro, making use of a laboratory strain of M. tuberculosis. METHODS: Spontaneous isoniazid-resistant mutants were characterized by molecular methods allowing identification of the most commonly encountered resistance-conferring mutations. Additionally, we determined the in vitro mutation rates for isoniazid and rifampicin resistance, and characterized the genome of a triple-resistant strain. RESULTS: Results confirm that the in vitro mutation rate for isoniazid resistance (3.2 x 10(-7) mutations/cell division) is much higher than the rate for rifampicin resistance (9.8 x 10(-9) mutations/cell division). However, in the majority of the in vitro mutants katG was partially or completely deleted and neither of the two most common in vivo mutations, katG-S315T or inhA-C(-)15T, were found in 120 isogenic mutants. This implies that clinically prevalent resistance mutations were present in <0.8% of isoniazid-resistant strains selected in vitro (95% CI 0%-2.5%). The triple-resistant strain had acquired isoniazid resistance via a 49 kbp deletion, which included katG. Apart from previously identified resistance-conferring mutations, three additional point mutations were acquired during sequential selection steps. CONCLUSIONS: These outcomes demonstrate that the in vivo mechanism of isoniazid resistance is not reflected by in vitro experiments. We therefore conclude that the high in vitro mutation rate for isoniazid resistance is not a satisfactory explanation for the fact that isoniazid monoresistance is significantly more widespread than monoresistance to rifampicin.

Cost-effectiveness analysis of PCR for the rapid diagnosis of pulmonary tuberculosis.

BACKGROUND: Tuberculosis is one of the most prominent health problems in the world, causing 1.75 million deaths each year. Rapid clinical diagnosis is important in patients who have co-morbidities such as Human Immunodeficiency Virus (HIV) infection. Direct microscopy has low sensitivity and culture takes 3 to 6 weeks 123. Therefore, new tools for TB diagnosis are necessary, especially in health settings with a high prevalence of HIV/TB co-infection. METHODS: In a public reference TB/HIV hospital in Brazil, we compared the cost-effectiveness of diagnostic strategies for diagnosis of pulmonary TB: Acid fast bacilli smear microscopy by Ziehl-Neelsen staining (AFB smear) plus culture and AFB smear plus colorimetric test (PCR dot-blot).From May 2003 to May 2004, sputum was collected consecutively from PTB suspects attending the Parthenon Reference Hospital. Sputum samples were examined by AFB smear, culture, and PCR dot-blot. The gold standard was a positive culture combined with the definition of clinical PTB. Cost analysis included health services and patient costs. RESULTS: The AFB smear plus PCR dot-blot require the lowest laboratory investment for equipment (US$ 20,000). The total screening costs are 3.8 times for AFB smear plus culture versus for AFB smear plus PCR dot blot costs (US$ 5,635,760 versus US$ 1,498, 660). Costs per correctly diagnosed case were US$ 50,773 and US$ 13,749 for AFB smear plus culture and AFB smear plus PCR dot-blot, respectively. AFB smear plus PCR dot-blot was more cost-effective than AFB smear plus culture, when the cost of treating all correctly diagnosed cases was considered. The cost of returning patients, which are not treated due to a negative result, to the health service, was higher in AFB smear plus culture than for AFB smear plus PCR dot-blot, US$ 374,778,045 and US$ 110,849,055, respectively. CONCLUSION: AFB smear associated with PCR dot-blot associated has the potential to be a cost-effective tool in the fight against PTB for patients attended in the TB/HIV reference hospital.

Barriers to Accessing Internationally Controlled Essential Medicines in Uganda: A Qualitative Study.

CONTEXT: Access to internationally controlled essential medicines is a problem worldwide. More than five billion people cannot access opioids for pain and palliative care or do not have access to surgical care or anesthetics, 25 million people living with epilepsy do not have access to their medicines, and 120,000 women die annually owing to postpartum hemorrhage. In Uganda, access to controlled medicines is also problematic, but a lack of data on factors that influence access exists. OBJECTIVES: The objective of this study was to identify the social, cultural, and regulatory barriers that influence access to internationally controlled essential medicines in Uganda. METHODS: Semistructured interviews with 15 key stakeholders with knowledge on controlled medicines from relevant institutions in Uganda. Interviews were transcribed verbatim and analyzed using the Access to Medicines from a Health System Perspective framework. RESULTS: Barriers in accessing controlled medicines were experienced owing to lack of prioritization, difficulties in finding the balance between access and control, deficiencies in the workings of the estimate and distribution system, lack of knowledge, inadequate human resources, expenses related to use and access, and stigma. It was believed that some abuse of specific controlled medicines occurred. CONCLUSION: The findings of this research indicate that to improve access to internationally controlled essential medicines in Uganda, health system strengthening is needed on multiple fronts. Active engagement and concerted efforts are needed from all stakeholders to ensure access and prevent abuse.

Extra-pulmonary tuberculosis: A retrospective study of patients in Accra, Ghana.

BACKGROUND: Information on extrapulmonary TB (EPTB) patients is limited in many African countries including Ghana. The study objective was to describe the epidemiology of EPTB patients diagnosed from different categories of health facilities in Accra, Ghana compared to pulmonary TB (PTB) patients and identify risk factors for mortality among EPTB patients. METHOD: We conducted retrospective analyses of demographic and clinical data accessed from medical records of EPTB and PTB patients from different types of health facilities from June 2010 to December 2013. Factors at diagnosis associated with EPTB compared to pulmonary TB (PTB) and factors associated with treatment outcome death among EPTB patients were assessed using logistic regression. RESULTS: Out of 3,342 new TB patients ≥15 years diagnosed, 728 (21.8%) had EPTB with a male: female ratio of 1.17. The EPTB sites commonly affected were disseminated 32.8%, pleura 21%, spine 13%, and Central Nervous System (CNS) 11%. Treatment success rate for EPTB was 70.1% compared to 84.2% for PTB (p<0.001). In logistic regression, HIV positivity (adjusted Odds Ratio [aOR] 3.19; 95% confidence interval [CI] 2.69-3.79) and female gender (aOR 1.59; 95% CI 1.35-1.88) were found to be significantly associated with EPTB compared with PTB. Older age, being HIV positive (aOR 3.15; 95% CI 1.20-8.25) and having CNS TB (aOR 3.88; 95% CI 1.14-13.23) were associated with mortality among EPTB patients. While more EPTB patients were diagnosed in the tertiary hospital, health facility type was not associated with mortality. CONCLUSION: EPTB patients in Accra have a worse treatment outcome compared to PTB patients with mortality of EPTB being associated with HIV, older age and CNS TB. Being HIV positive and female gender were found to be significantly associated with EPTB. Increased awareness of these factors may facilitate early case finding and better management outcomes for these patients.

Yield of tuberculosis among household contacts of tuberculosis patients in Accra, Ghana.

BACKGROUND: The End TB Strategy calls for systematic screening of selected high-risk groups including contacts of tuberculosis (TB) cases to facilitate early TB case detection. Contact investigation is not usually routinely practiced in low TB burden countries, such as Ghana, with consequent paucity of data on the yield of TB case detection from such interventions. This study's objective was to document the outcomes and feasibility of implementing contact investigation activities under programmatic conditions in Ghana. METHODS: Retrospective analyses were conducted of abstracted data from the National TB Program, following a contact investigation intervention for TB cases diagnosed in 10 facilities in Accra from June 2010 to December 2014. Various proportions and yield from number of contacts needed to screen (NNS) and number needed to test (NNT) to detect a TB case were assessed. RESULTS: Overall, out of the 8519 listed contacts of 3267 index cases, 8166 (96%) were screened and 614 (7.5%) were identified as presumptive TB. Out of these, 438 (71%) underwent sputum smear microscopy/evaluation and 53 TB cases were diagnosed. Of these, 56.6% were males, and 49% had sputum smear-positive TB, 38% had sputum smear-negative TB, and 7% had extra-pulmonary TB. The NNS and NNT to detect a TB case of all forms were 154 and 8, respectively. The proportion of TB cases with contacts listed and proportion of contacts screened annually were 88-96% and 83-100%, respectively. The proportion of presumptive TB cases tested and proportion of TB cases diagnosed among contacts tested that were 100% and 36%, respectively, in 2010 dropped to 40% and 14%, respectively, by 2014. CONCLUSIONS: The study demonstrates that contact identification and prioritization components of a contact investigation were feasible, but overall yield of TB cases may have been lower due to the declining rate of clinical evaluation of presumptive TB contacts over time. Addressing barriers to accessing appropriate diagnostic tests may enhance yield from contact investigation in Ghana.

Insufficient Fruit and Vegetable Intake in a Low- and Middle-Income Setting: A Population-Based Survey in Semi-Urban Tanzania.

A daily intake of 5 portions of fruit and vegetables (FV) is recommended for protection against non-communicable diseases (NCDs). Inadequate FV intake is a global problem but resource-poor countries like Tanzania are most deprived and constitute settings where little is known for informing public health interventions. This study aimed to describe the prevalence of inadequate FV intake, frequency of FV intake, portions of FV intake and their associations with socio-demographic/lifestyle factors in South-Eastern Tanzania. Data on FV dietary indicators, socio-demographic factors, smoking, alcohol and healthcare use were collected from 7953 participants (≥15 years) of the population-based MZIMA open community cohort (2012-2013). Multivariable logistic regression was used to examine associations between FV intake outcomes and their socio-demographic/lifestyle determinants. Most (82%) of the participants did not meet the recommended daily FV intake While only a fraction consumed fruits daily (15.5%), almost half consumed vegetables daily (44.2%). However, the median (IQR) number of vegetable portions consumed was lower (2(1)/person/day) than that for fruits (2(2)/person/day) People with higher education were more likely to consume fruits daily. Independent correlates of inadequate FV intake included young age, being male, low education, low-income occupations, low alcohol, high tobacco and low healthcare use. Public health interventions should target the socio-economically deprived and culturally-rooted preferences while prioritizing promotion of vegetable for most immediate gain in overall FV intake.

A Cross-Sectional Examination of Physical Activity Levels and Their Socio-Demographic Determinants in Southern Tanzania.

Physical activity is essential for healthy aging. Evidence suggests that vigorous-intensity physical activity (VPA) may be more beneficial than moderate-intensity physical activity (MPA). We examined physical activity levels (MPA, VPA and total physical activity), and their socio-demographic determinants in 2311 participants (15⁻93 years; 68% women) of the MZIMA Open Community Cohort, who had complete relevant data. Physical activity levels were estimated in minutes per week across three domains—work, leisure and transport. We created three outcome variables: low MPA (<150 min per week of MPA), low VPA (<75 min per week of VPA) and insufficient physical activity (IPA: <150 min per week of total physical activity) and applied sample-weighted multivariable logistic regression to assess associations with potential socio-demographic determinants. Prevalence of IPA, low MPA and low VPA were 25%, 26% and 65% respectively. IPA and low MPA were correlated (Spearman R = 0.98; p < 0.001). Work, leisure and transport contributed 54%, 25% and 21% to total physical activity respectively. IPA and low VPA were significantly associated with female sex, lower education, non-manual occupation and frequent fruit consumption. We observed significant differences by sex (Pheterogeneity < 0.001), on the associations between education and IPA, and between age, occupation and low VPA. In conclusion, low levels of VPA, which were more pronounced in women, support the monitoring and promotion of VPA alongside overall physical activity. Leisure-related activities should also be promoted towards gains in vigorous-intensity and total physical activity in this setting.

Specific mutations in the Mycobacterium tuberculosis rpoB gene are associated with increased dnaE2 expression.

In Mycobacterium tuberculosis (MTB), rifampicin resistance is almost invariably due to mutations in the rpoB gene, whose function is critical for cell viability. Most of these mutations, at least initially, impair the fitness of the bacteria but confer a selective advantage when antibiotic pressure is exerted. Subsequent adaptation may be critical to restore fitness. The possibility was considered that MTB with mutations in the rpoB gene elicits a constitutive stress response, increasing the probability of subsequent adaptation. In order to test this hypothesis, the expression of recA and dnaE2, an inducible putative error-prone DNA polymerase, was determined in six different isogenic laboratory-generated rpoB-mutants of MTB. Expression levels were determined with real-time PCR and the data obtained were compared with those of the wild-type parent. In four of the six rpoB mutants, a two- to fivefold induction of dnaE2 was detected (P<0.05). Thus, the presence of specific mutations in rpoB is not only associated with impaired fitness but also results in a detectable, moderate yet persistent increase in the expression of dnaE2 but not recA.

The ML flow test as a point of care test for leprosy control programmes: potential effects on classification of leprosy patients.

OBJECTIVE: To evaluate the use of the ML Flow test as an additional, serological, tool for the classification of new leprosy patients. DESIGN: In Brazil, Nepal and Nigeria, 2632 leprosy patients were classified by three METHODS: : (1) as multibacillary (MB) or paucibacillary (PB) according to the number of skin lesions (WHO classification), (2) by slit skin smear examination, and (3) by serology using the ML Flow test detecting IgM antibodies to Mycobacterium leprae-specific phenolic glycolipid-I. RESULTS: The proportion of MB leprosy patients was 39.5, 35.6 and 19.4% in Brazil, Nepal and Nigeria, respectively. The highest seropositivity in patients was observed in Nigeria (62.9%), followed by Brazil (50.8%) and Nepal (35.6%). ML Flow test results and smears were negative in 69.1 and 82.7% of PB patients, while smears were positive in 58.6% of MB patients in Brazil and 28.3% in Nepal. In MB patients, both smears and ML Flow tests were negative in 15.6% in Brazil and 38.3%, in Nepal. Testing all PB patients with the ML Flow test to prevent under-treatment would increase the MB group by 18, 11 and 46.2% for Brazil, Nepal and Nigeria, respectively. Using the ML Flow test as the sole criterion for classification would result in an increase of 11.3 and 43.5% of patients requiring treatment for MB leprosy in Brazil and Nigeria, respectively, and a decrease of 3.7% for Nepal. CONCLUSIONS: The ML Flow test could be used to strengthen classification, reduce the risk of under-treatment and minimize the need for slit skin smears.