Hematological profiles of patients with tuberculosis and nontuberculous mycobacteria infections in Bamako, Mali.

Background: Pulmonary tuberculosis (TB) remains one of the main causes of morbidity and mortality in Mali. Nontuberculous mycobacteria (NTM) infections are very common but are often cofounded with TB because of the similarity of symptoms, which makes the diagnosis difficult. Hematological abnormalities associated with TB have been described, but not with NTM. Therefore, the goal of this study was to compare the hematological parameters of patients infected with TB and NTM infections. Methods: A cross-sectional study enrolling TB and NTM participants was conducted in 2018-2020. Five milliliters of venous blood and sputum samples were collected from each participant to determine the hematological parameters using the RUBY CELL-DYN Ruby Version 2.2 ML. A BACTEC MGIT 960 and multiplex reverse transcription-polymerase chain reaction were used to distinguish Mycobacterium tuberculosis from NTM, respectively. Results: Of the total 90 patients enrolled, there was a decrease in hemoglobin and hematocrit levels in both the groups (P = 0.05). In addition, we found that the percentages of basophil cells (P = 0.01) and mean values of platelets (P = 0.04) were significantly higher in TB patients than those of NTMs. Moreover, the mean of absolute values of eosinophil cells of TB patients was significantly lower than those of NTMs (P = 0.03). Conclusion: We found significant statistical differences in basophils, platelets, and eosinophils in differentiating TB and NTM in this pilot study. Future studies with patients at different clinical stages are needed to confirm the hematological profiles of TB and NTM patients.

Relationship between patient sex and anatomical sites of extrapulmonary tuberculosis in Mali.

Background: Contribution of host factors in mediating susceptibility to extrapulmonary tuberculosis is not well understood. Objective: To examine the influence of patient sex on anatomical localization of extrapulmonary tuberculosis. Methods: We conducted a retrospective cross-sectional study in Mali, West Africa. Hospital records of 1,304 suspected cases of extrapulmonary tuberculosis, available in TB Registry of a tertiary tuberculosis referral center from 2019 to 2021, were examined. Results: A total of 1,012 (77.6%) were confirmed to have extrapulmonary tuberculosis with a male to female ratio of 1.59:1. Four clinical forms of EPTB predominated, namely pleural (40.4%), osteoarticular (29.8%), lymph node (12.5%), and abdominal TB (10.3%). We found sex-based differences in anatomical localization of extrapulmonary tuberculosis, with males more likely than females to have pleural TB (OR: 1.51; 95% CI [1.16 to 1.98]). Conversely, being male was associated with 43% and 41% lower odds of having lymph node and abdominal TB, respectively (OR: 0.57 and 0.59). Conclusion: Anatomical sites of extrapulmonary tuberculosis differ by sex with pleural TB being associated with male sex while lymph node and abdominal TB are predominately associated with female sex. Future studies are warranted to understand the role of sex in mediating anatomical site preference of tuberculosis.

Clinical evaluation of commercial SARS-CoV-2 serological assays in a malaria endemic setting.

The levels of immune response to SARS-CoV-2 infection or vaccination are poorly understood in African populations and is complicated by cross-reactivity to endemic pathogens as well as differences in host responsiveness. To begin to determine the best approach to minimize false positive antibody levels to SARS-CoV-2 in an African population, we evaluated three commercial assays, namely Bio-Rad Platelia SARS-CoV-2 Total Antibody (Platelia), Quanterix Simoa Semi-Quantitative SARS-CoV-2 IgG Antibody Test (anti-Spike), and the GenScript cPass™ SARS-CoV-2 Neutralization Antibody Detection Kit (cPass) using samples collected in Mali in West Africa prior to the emergence of SARS-CoV-2. A total of one hundred samples were assayed. The samples were categorized in two groups based on the presence or absence of clinical malaria. Overall, thirteen out of one hundred (13/100) samples were false positives with the Bio-Rad Platelia assay and one of the same one hundred (1/100) was a false positive with the anti-Spike IgG Quanterix assay. None of the samples tested with the GenScript cPass assay were positive. False positives were more common in the clinical malaria group, 10/50 (20%) vs. the non-malaria group 3/50 (6%); p = 0.0374 using the Bio-Rad Platelia assay. Association between false positive results and parasitemia by Bio-Rad remained evident, after adjusting for age and sex in multivariate analyses. In summary, the impact of clinical malaria on assay performance appears to depend on the assay and/or antigen being used. A careful evaluation of any given assay in the local context is a prerequisite for reliable serological assessment of anti-SARS-CoV-2 humoral immunity.

Prevalence and Clinical Relevance of Schistosoma mansoni Co-Infection with Mycobacterium tuberculosis: A Systematic Literature Review.

Tuberculosis disease stands for the second leading cause of death worldwide after COVID-19, most active tuberculosis cases result from the reactivation of latent TB infection through impairment of immune response. Several factors are known to sustain that process. Schistosoma mansoni, a parasite of the helminth genus that possesses switching power from an immune profile type Th1 to Th2 that favors reactivation of latent TB bacteria. The aim of the study was to assess the prevalence of the co-infection between the two endemic infections. Systematic literature was contacted at the University Clinical Research Center at the University of Sciences, Techniques, and Technologies of Bamako in Mali. Original articles were included, and full texts were reviewed to assess the prevalence and better understand the immunological changes that occur during the co-infection. In total, 3530 original articles were retrieved through database search, 53 were included in the qualitative analysis, and data from 10 were included in the meta-analysis. Prevalence of the co-infection ranged from 4% to 34% in the literature. Most of the articles reported that immunity against infection with helminth parasite and more specifically Schistosoma mansoni infection enhances latent TB reactivation through Th1/Th2. In sum, the impact of Schistosoma mansoni co-infection with Mycobacterium tuberculosis is under-investigated. Understanding the role of this endemic tropical parasite as a contributing factor to TB epidemiology and burden could help integrate its elimination as one of the strategies to achieve the END-TB objectives by the year 2035.

Sex Differences in Active Pulmonary Tuberculosis Outcomes in Mali, West Africa.

Men and women often respond differently to infectious diseases and their treatments. Tuberculosis (TB) is a life-threatening communicable disease that affects more men than women globally. Whether male sex is an independent risk factor for unfavorable TB outcomes, however, has not been rigorously investigated in an African context, where individuals are likely exposed to different microbial and environmental factors. We analyzed data collected from a cohort study in Mali by focusing on newly diagnosed active pulmonary TB individuals who were treatment naive. We gathered baseline demographic, clinical, and microbiologic characteristics before treatment initiation and also at three time points during treatment. More males than females were affected with TB, as evidenced by a male-to-female ratio of 2.4:1. In addition, at baseline, males had a significantly higher bacterial count and shorter time to culture positivity as compared with females. Male sex was associated with lower smear negativity rate after 2 months of treatment also known as the intensive phase of treatment, but not at later time points. There was no relationship between patients' sex and mortality from any cause during treatment. This study suggests that sex-based differences in TB outcomes exist, with sex-specific effects on disease outcomes being more pronounced before treatment initiation and during the intensive phase of treatment rather than at later phases of treatment.

Molecular epidemiology and genetic diversity of Mycobacterium tuberculosis complex in referral health centers of Bamako, Mali: What is new?

BACKGROUND AND AIMS: Tuberculosis (TB) remains an important global health issue worldwide. Despite this scourge threatening many human lives, especially in developing countries, thus far, no advanced molecular epidemiology study using recent and more accurate tools has been conducted in Mali. Therefore, this study aimed to use variable-number tandem repeats of mycobacterial interspersed repetitive units (MIRU-VNTR) technology coupled with the spoligotyping method to accurately determine the hot spots and establish the epidemiological transmission links of TB in Bamako, Mali. METHODS: In a cross-sectional study, 245 isolates of Mycobacterium tuberculosis complex (MTBC) were characterized using spoligotyping and MIRU-VNTR, and an epidemiological investigation was conducted. RESULTS: Of the 245 isolates, 184 (75.1%) were formally identified. The most widespread strain was the Cameroon strain (83; 45.1%). Eight major clusters were identified: Ghana (27; 14.7%), West African 2 (22; 12%), Haarlem (13; 7.1%), H37Rv (t) (8; 4.3%), Latin American Mediterranean (8; 4.3%), and Uganda I and II (6; 3.3%). Statistical analysis showed a significant difference between lineages from the respective referral health centers of Bamako, Mali (P = 0.01). CONCLUSION: This study establishes, for the first time, an accurate spatial distribution of circulating MTB strains in Bamako, Mali. The data was used to identify strains and "hot spots" causing TB infection and can also be used for more targeted public health responses, particularly for hot spots of drug-resistant strains.

High SARS-CoV-2 Seroprevalence among Healthcare Workers in Bamako, Mali.

In Mali, a country in West Africa, cumulative confirmed COVID-19 cases and deaths among healthcare workers (HCWs) remain enigmatically low, despite a series of waves, circulation of SARS-CoV-2 variants, the country's weak healthcare system, and a general lack of adherence to public health mitigation measures. The goal of the study was to determine whether exposure is important by assessing the seroprevalence of anti-SARS-CoV-2 IgG antibodies in HCWs. The study was conducted between November 2020 and June 2021. HCWs in the major hospitals where COVID-19 cases were being cared for in the capital city, Bamako, Mali, were recruited. During the study period, vaccinations were not yet available. The ELISA of the IgG against the spike protein was optimized and quantitatively measured. A total of 240 HCWs were enrolled in the study, of which seropositivity was observed in 147 cases (61.8%). A continuous increase in the seropositivity was observed, over time, during the study period, from 50% at the beginning to 70% at the end of the study. HCWs who provided direct care to COVID-19 patients and were potentially highly exposed did not have the highest seropositivity rate. Vulnerable HCWs with comorbidities such as obesity, diabetes, and asthma had even higher seropositivity rates at 77.8%, 75.0%, and 66.7%, respectively. Overall, HCWs had high SARS-CoV-2 seroprevalence, likely reflecting a "herd" immunity level, which could be protective at some degrees. These data suggest that the low number of cases and deaths among HCWs in Mali is not due to a lack of occupational exposure to the virus but rather related to other factors that need to be investigated.

Relationships between gut microbiota, red meat consumption and colorectal cancer.

Excessive consumption of red and processed meat has been associated with a higher risk of developing colorectal cancer. There are many attempts to explain the risk of colorectal cancer associated with the consumption of red and processed meat: The temperature cooking of meat such as grilling and smoking contribute to the formation of mutagenic compounds including heterocyclic amines and polycyclic aromatic hydrocarbons.Heme iron in red meat is involved in the formation of N-nitroso compounds and lipid peroxidation products in the digestive tract.Fatty red meat is involved in the production of secondary bile acids by the bacteria of the gut microbiota. Many of the products formed are genotoxic and can cause DNA damage and initiate carcinogenesis of colorectal cancer. Various mechanisms contributing to their genotoxic role have been established in human and animal studies. In addition, there is increasing evidence that compounds formed from red and processed meat interact with the gut microbiota in colorectal cancer pathways. Although several early studies in animals and humans suggest a direct causal role of the gut microbiota in the development of colorectal cancer, the links between diet, gut microbiota, and colonic carcinogenesis are largely associations rather than proven causal relationships. Various biological mechanisms, including inflammation and oxidative stress can lead to DNA damage, gut dysbiosis, and therefore increase the risk of colorectal cancer. Dysbiosis of the gut microbiota may increase the risk of colorectal cancer through dietary component promotion of colonic carcinogenesis. In this paper, we review and update current knowledge about the relationships between red meat consumption, gut microbiota, and colorectal cancer.

Antituberculosis Therapy and Gut Microbiota: Review of Potential Host Microbiota Directed-Therapies.

Tuberculosis (TB) remains a major public health concern with millions of deaths every year. The overlap with HIV infections, long treatment duration, and the emergence of drug resistance are significant obstacles to the control of the disease. Indeed, the standard first-line regimen TB treatment takes at least six months and even longer for the second-line therapy, resulting in relapses, drug resistance and re-infections. Many recent reports have also shown prolonged and significant damage of the gut microbial community (dysbiosis) from anti-TB drugs that can detrimentally persist several months after the cessation of treatment and could lead to the impairment of the immune response, and thus re-infections and drug resistance. A proposed strategy for shortening the treatment duration is thus to apply corrective measures to the dysbiosis for a faster bacterial clearance and a better treatment outcome. In this review, we will study the role of the gut microbiota in both TB infection and treatment, and its potential link with treatment duration. We will also discuss, the new concept of "Host Microbiota Directed-Therapies (HMDT)" as a potential adjunctive strategy to improve the treatment effectiveness, reduce its duration and or prevent relapses. These strategies include the use of probiotics, prebiotics, gut microbiota transfer, and other strategies. Application of this innovative solution could lead to HMDT as an adjunctive tool to shorten TB treatment, which will have enormous public health impacts for the End TB Strategy worldwide.

Development and clinical evaluation of a new multiplex PCR assay for a simultaneous diagnosis of tuberculous and nontuberculous mycobacteria.

BACKGROUND: The prevalence of non-tuberculous mycobacteria (NTM) has been increasing worldwide in both developed and developing countries. NTM infection is clinically indistinguishable from tuberculosis and therefore poses significant challenges in patient management, especially in patients chronically treated for pulmonary TB. In this study, we evaluated a new highly sensitive Multiplex MTB/NTM assay that can differentiate M. tuberculosis complex (MTBC) from all NTM, including the treatable and most common NTM, M. avium complex (MAC). METHODS: We developed and optimized a new open- Multiplex MTB/NTM assay with two gene-targets for MTBC (IS6110/senX3-regX3) and two targets for MAC (IS1311/DT1) with samples spiked with stored strains and testing 20 replicates. Patients with presumptive TB and NTM were enrolled at the Respiratory Disease Department of The University Teaching Hospital of Point G, in Mali. FINDINGS: In the development stage, the new assay showed a high analytic performance with 100% detections of MTBC and MAC at only 5 colony forming units (CFUs). Overall, without the treatment failure cases, the Multiplex assay and the Xpert showed a sensitivity, specificity, PPV and NPV of 83·3% [66·4-92·6], 96·6% [88·6-99·0], 92·5% [82·3-96·5] and 92·2% [82·7-96·5] and the Xpert had values of 96·7% [83·3-99·4], 80·0% [68·2-88·1], 70·7 [55·5-82·3] and 97·9% [89·3-99·6], respectively. The Multiplex assay successfully detected all (5/5) the MAC cases. INTERPRETATION: Our new Multiplex assay demonstrates better specificity than Xpert for all group studied, in addition to detecting potential NTM cases. The assay could therefore complement the widely used Xpert assay and enhance discrimination of TB and NTM infections. FUNDING: This work was supported by the National Institutes of Health (R03AI137674, U54EB027049, D43TW010350 and UM1AI069471) and Northwestern University's Institute for Global Health Catalyzer Fund.

[Study on the clinical and epidemiological characteristics of the first 1030 cases of covid-19 in Mali]. / Etude sur les caracteristiques cliniques et epidemiologiques des 1030 premiers cas de covid-19 au Mali.

AIMS: Since the confirmation of the first cases of COVID-19 in Mali in March 2020 and the outbreakspreading to the whole country, clinical and epidemiological data fromaffected patients are used to characterize the disease. This study was to describe the clinica lsigns and epidemiologicalparameters of COVID-19 in the Malian context. MATERIALS AND METHODS: This is a cross-sectional study. All confirmed cases of COVID-19 in Mali between March 25, 2020 to May 24, 2020 have been included. Clinical and epidemiological data from patients with COVID-19 were extracted from the official line list of cases and the national reference laboratory register. RESULTS: The mean age of the 1,030 patients was 45.6 ± 18.4 years; 67.2% of patients were men. Asymptomatic patients accounted for 31.1%. The most common symptoms on admission were cough (60.8%) followed by fever (47.6%). The largest number of cases was recorded in Bamako. CONCLUSION: SARS-CoV-2 infection of the first 1,030 cases in Mali was marked by the predominance of cough and fever.

BUTS: Depuis la confirmation des premiers cas de COVID-19 au Mali en Mars 2020 et sa propagation à tout le pays, des données cliniques et épidémiologiques des patients atteints sont utilisées pour caractériser la maladie. Cette étude avait pour objectif d'étudier les signes cliniques et épidémiologiques de la COVID-19 dans le contexte malien. MATÉRIELS ET MÉTHODES: Il s'agit d'une étude transversale. Tous les cas confirmés de COVID-19 du Mali entre le 25 Mars 2020 au 24 Mai 2020 ont été inclus. Les données cliniques et épidémiologiques des patients atteints de COVID-19ont été extraites. RÉSULTATS: L'âge moyen descas était de 45,6±18,4 ans ; 67,2% des patients étaient des hommes. Les patients asymptomatiques représentaient 31,1%. Les symptômes les plus courants à l'admission étaient la toux (60,8%) suivi de la fièvre (47,6%). Le plus grand nombre de cas a été enregistré à Bamako. CONCLUSION: L'infection par le SARS-CoV-2 des 1 030 premiers cas au Mali a été marquée par la prédominance de la toux et de la fièvre.

[Clinical and epidemiological characteristic of COVID-19 deaths in Mali]. / Caracteristiques clinique et epidemiologique des deces COVID-19 au Mali.

INTRODUCTION: Mali recorded its first COVID-19's death related case on March 26, 2020. The aim of this study was to evaluate the comorbidity of COVID-19's death related cases in the Malian context. METHOD: A cross-sectional study was conducted between March 25 and October 11, 2020. Community death information was analyzed from the patient descriptive list, and from the hospitalization registry of the treatment sites. RESULT: Of the 3,286 COVID-19 confirmed cases, 132 died making a lethality rate of 4.00% (132/3286). Men were the most represented with 75.76% (100/132). The mean age was 63.77 ± 15.25 years. The mean time of hospital stay was 4.50 days ± 6.35. Diabetes and cardiovascular disease remain the most frequent comorbidities with death patients with 20.45% and 17.42%, respectively. CONCLUSION: The results of this study allow to draw map of patients who died from COVID-19 as well as provide information on the comorbidities for better management of hospitalized patients.

INTRODUCTION: Le Mali a enregistré son premier cas de décès lié à la COVID-19, le 26 mars 2020.Le but de cette étude est d'étudier la comorbidité des cas de décès de COVID-19 dans le contexte malien. MÉTHODE: Il s'agissait d'une étude transversale allant de la période du 25 mars au 11 octobre 2020. Nous avons réalisé une analyse des informations de la liste descriptives des cas pour les décès communautaire et des registres d'hospitalisation des sites de prise en charge. RÉSULTAT: Sur les 3286 cas confirmés par la COVID-19, 132 malades en sont décédés soit une létalité de4,00%. Les hommes étaient les plus représentés avec 75,76 % (100/132). La moyenne d'âge était de 63,77 ans ± 15,25. La durée moyenne d'hospitalisation était de4,50 jours ± 6,35. Le diabète et l'HTA étaient les facteurs de comorbidité les plus fréquents rencontrés dans les cas de décès avec respectivement 20,45% et 17,42%. CONCLUSION: Cette étude a montré que les cas de décès liés au COVID-19 au Mali étaient observés chez les personnes âgées, diabétiques et hypertendues. Ces informations aideront à optimiser la prise en charge des malades hospitalisés.

Short Communication: Genetic Variation in Human IL10 Proximal Promoter and Susceptibility to HIV-1 Infection in Mali, West Africa.

It is now recognized that to fully understand the role of host genetic variation on susceptibility to HIV-1 infection, investigations must be extended to African populations. We sought to determine if genetic variation in IL10 are associated with HIV-1 infection in a West African cohort in Mali. HIV-infected and -uninfected individuals were genotyped for three common single nucleotide polymorphisms (SNPs) located at positions -592 (C/A), -819 (C/T), and -1082 (G/A) of the IL10 promoter. We found that the ATA haplotype, which has been previously associated with low IL-10 expression, was the most represented in the cohort. Although we observed a trend toward an increased frequency of ATA/ATA carriage in HIV-infected compared with -uninfected individuals, the difference was not statistically significant. Similarly, individual IL10 SNPs were not significantly enriched in the HIV-infected group, suggesting that IL10 genetic variants are not associated with HIV-1 in this West African cohort from Mali.

Exploring the usefulness of molecular epidemiology of tuberculosis in Africa: a systematic review.

BACKGROUND: Tuberculosis (TB) is caused by Mycobacterium tuberculosis complex (MTBC) and remains a serious global public health threat, especially in resource-limited settings such as the African region. Recent developments in molecular epidemiology tools have significantly improved our understanding of TB transmission patterns and revealed the high genetic diversity of TB isolates across geographical entities in Africa. This study reports the results of a systematic review of current knowledge about MTBC strain diversity and geographical distribution in African regions. METHODS: Search tools (PubMed, Embase, Popline, OVID and Africa Wide Information) were employed to identify the relevant literature about prevalence, strain diversity, and geographic distribution of MTBC infection in Africa. RESULTS: A total of 59 articles from 739 citations met our inclusion criteria. Most articles reported about patients with presumptive pulmonary TB (73%), fewer reports were on retreatment and treatment failure cases (12%), and presumptive drug resistance cases (3%). Spoligotyping was the most used, alone in 21 studies and in parallel with either the Mycobacterial Interspersed Repetitive Units Variable Number of Tandem Repeats or the Restriction Fragment Length Polymorphism. Various TB lineages were observed across the African continent, with the originally European lineage 4 spotted in all countries studied. CONCLUSION: TB molecular epidemiology tools have substantially improved our understanding of the MTBC circulating isolates, their evolution, and diversity in this highly endemic region of Africa. We found that only TB lineage 4 is present throughout all the continent and the clusters identified provides an extended insight into the disease transmission dynamics.

Patients infected with Mycobacterium africanum versus Mycobacterium tuberculosis possess distinct intestinal microbiota.

BACKGROUND: Mycobacterium tuberculosis complex (MTBC), the causative agent of tuberculosis (TB), is composed of eight subspecies. TB in West Africa, in contrast to other geographical regions, is caused by Mycobacterium africanum (MAF) in addition to M. tuberculosis (MTB), with both infections presenting similar symptoms. Nevertheless, MAF is considered to be hypovirulent in comparison with MTB and less likely to progress to active disease. In this study, we asked whether MAF and MTB infected patients possess distinct intestinal microbiomes and characterized how these microbiota communities are affected by anti-tuberculosis therapy (ATT). Additionally, we assessed if the changes in microbiota composition following infection correlate with pathogen induced alterations in host blood-gene expression. METHODS: A longitudinal, clinical study of MAF infected, MTB infected patients assessed at diagnosis and two months after start of ATT, and healthy, endemic controls was conducted to compare compositions of the fecal microbiome as determined by 16S rRNA sequencing. A blood transcriptome analysis was also performed on a subset of subjects in each group by microarray and the results cross-compared with the same individual's microbiota composition. FINDINGS: MAF participants have distinct microbiomes compared with MTB patients, displaying decreased diversity and increases in Enterobacteriaceae with respect to healthy participants not observed in the latter patient group. Interestingly, this observed elevation in Enterobacteriaceae positively correlated with enhanced inflammatory gene expression in peripheral blood and was reversed after initiation of ATT. INTERPRETATION: Our findings indicate that MAF and MTB have distinct associations with the gut microbiome that may be reflective of the differential susceptibility of West Africans to these two co-endemic infections either as biomarkers or as a contributing determinant.

Performance Comparison of Xpert HIV-1 Viral Load Assay and Roche Taqman and Abbott M2000 RT in Bamako, Mali.

BACKGROUND: Routine monitoring of HIV-1 Viral Load (VL) is important in patients on Antiretroviral Therapy (ART) management. Access to HIV VL remains a challenge in resource-limited settings, especially in rural areas. Universal access to VL requires more simplified and less restrictive alternatives to current conventional VL methods. The objective of this study was to evaluate the performance of the new rapid (2-hour turnaround time) Xpert HIV-1VL technique compared to Roche TaqMan and Abbott RT m2000 for HIV-1 RNA quantification in HIV- infected patients. STUDY DESIGN: We conducted a cross-sectional study in patients seen for routine VL monitoring between August and November 2018 in a HIV care site in Bamako. The performance of the Xpert HIV-1 VL assay was evaluated against the Roche TaqMan assay and Abbott m2000 RT assay. Performance, utility and reliability/reproducibility were verified using accuracy, sensitivity, specificity, positive and negative predictive values, Diagnostic Odds Ratio (DOR), Kappa coefficient, Pearson correlation coefficient, and Bland-Altman analysis. RESULTS: The Xpert assay compared well with the two current referral assays (Roche TaqMan and Abbott m2000 RT assays). Compared to Roche TaqMan assay the sensitivity was 93.10%, specificity (97.01%) and accuracy (95.20%), the correlation coefficient of Pearson (r) was 0.98 (p <0.01). Bland-Altman analysis showed a mean difference of 0.18 log10 cp/mL; (Standard Deviation) SD=0.33. Compared to the Abbott m2000 RT, the sensitivity, the specificity and the accuracy were respectively 93.44%; 92% and 92.65%. The Xpert HIV-1 VL assay showed a good correlation with a correlation coefficient of Pearson, r=0.99 (p <0.001). The overall mean difference in the HIV-1 VL values obtained by Xpert HIV-1 VL and Abbott m2000 RT assays was 0.08 log10 cp/mL; SD=0.30. CONCLUSION: Xpert HIV-1 VL showed a good performance compared to Roche TaqMan and Abbott m2000 RT. With the rapid test results (less than 2 h) and ease of testing individual specimens, the Xpert HIV-1 VL assay could be an effective alternative for HIV VL monitoring in resource-limited settings.

Diagnostic Laboratories' Capacities and Preparedness for Emerging Viral Diseases in Guinea and Mali.

The 2014-2016 Ebola epidemic in Guinea highlighted the need for more extensive evaluation of laboratories diagnostic capacities and preparedness in anticipation of future emerging viral disease outbreaks. We developed a questionnaire to assess the diagnostic capacities and preparedness of the four major medical laboratories in Guinea and Mali that are responsible for the provision of Ebola, Lassa, and Dengue diagnostics. The questionnaire inquired about the current state and need for equipment and reagents and adequacy of equipment and training received. In Guinea, all three diagnostic laboratories have the capacity and are well-prepared to perform Ebola diagnostics, however, only two have the capacity and trained staff to diagnose Lassa and none are currently prepared to diagnose Dengue infection. In Mali, the University Clinical Research Center (UCRC) laboratory, which was in charge of Ebola diagnostics during the last epidemic, currently has the capacity and is prepared to diagnose Ebola, Lassa, and Dengue infections. Combined, Guinea and Mali appear to have complementary capacity and preparedness to diagnose these Category A Priority Pathogens. While, the equipment, reagents and training efforts should be maintained, the gap in Dengue diagnostic capability in Guinea should be addressed with further equipping and training of additional district laboratories to strengthen the public health response for all viral diseases in these high-risk, yet, low-resource settings.

Association of Mycobacterium africanum Infection with Slower Disease Progression Compared with Mycobacterium tuberculosis in Malian Patients with Tuberculosis.

Mycobacterium africanum (MAF) is known to endemically cause up to 40-50% of all pulmonary TB in West Africa. The aim of this study was to compare MAF with Mycobacterium tuberculosis (MTB) with regard to time from symptom onset to TB diagnosis, and clinical and radiological characteristics. A cross-sectional study was conducted in Bamako, Mali, between August 2014 and July 2016. Seventy-seven newly diagnosed pulmonary TB patients who were naive to treatment were enrolled at Mali's University Clinical Research Center. Sputum cultures were performed to confirm the diagnosis and spoligotyping to identify the mycobacterial strain. Univariate and multivariate analyses were used to identify factors associated with disease progression. Overall, the frequency of female patients was 25% in MAF infection and only 10.0% in MTB infection (OR = 2.9), and MAF was more represented in patients aged ≥ 30 years (57.1% versus 36.7% [OR = 2.3]). More MAF- than MTB-infected patients had a history of a prior TB contact (32.1% versus 14.3% [OR = 2.8]). The mean duration between cough onset and TB diagnosis was 111 days (∼3.7 months) for MAF and 72 days (∼2.4 months) for MTB (P = 0.007). In a multivariate regression, weight loss (body mass index [BMI] < 18.5 kg/m2) and cough duration (> 4 months) were strongly associated with MAF infection (OR = 5.20 [1.49-18.26], P = 0.010, and 4.74 [1.2-18.58], P = 0.02), respectively. Our data show that MAF infection was significantly associated with lower BMI and a longer time between symptom onset and TB diagnosis than MTB. This supports the concept that MAF infection may have slower disease progression and less severe cough symptoms than MTB.

Use of sodium dodecyl sulfate to improve tuberculosis sputum smear microscopy.

Sputum smear microscopy (SSM), the most widely available tool for tuberculosis (TB) detection, has limited performance in paucibacillary patients and requires highly experienced technicians. The objective of this study was to determine whether the addition of sodium dodecyl sulfate (SDS), a detergent that thins sputum, at 4% and 10%, improves the detection of acid-fast bacilli (AFB), the clarity of slides, and the biosafety of the technique. Thirty participants with presumptive TB were enrolled. Three independent, blinded technicians examined the slides. Regular sputum concentrated AFB smear and sputum culture were used as standard control methods. Sputum culture was also performed before and after 10% SDS addition for safety analysis. We found that neither SSM with SDS 4% nor SSM with SDS 10% improved the test's performance. However, slides with 4% and 10% SDS, compared with slides prepared without SDS, had significantly better clarity scores. The 10% SDS-prepared sputum samples were all culture negative. While adding SDS detergent does not improve the performance of SSM slides, it does improve the clarity and biosafety. Where experienced technicians are scarce, especially in low resource settings, use of SDS may enhance the ease of slide reading in sputum smear microscopy.

Competitive fitness of Mycobacterium tuberculosis in vitro.

Background: While, bacteria resistance mutations can affect competitive fitness, given our multidrug-resistant (MDR) prevalence, we conducted this study to determine the impact of MDR on the competitive fitness of Mycobacterium tuberculosis (MTB) complex MDR strains. We conducted a cross-sectional study at the University Clinical Research Center (UCRC) from January to December 2017. New TB patients over aged of 18 were recruited at University teaching hospital and health reference centers of Bamako in USTTB Ethical committee approved protocols. Methods: MDR and drug-susceptible (wild-type [WT]) MTB strains (T1 and Beijing) and MTB H37Rv were competed on solid media in UCRC's Tuberculosis Laboratory. Competitive and individual cultures were incubated for 14 days at 37°C with 7% CO2. Number of generation, generation time, and relative competitive fitness (W) of the strains were calculated. Data were analyzed with Epi-Info 7.1.5.2 software (CDC). P value was considered significant when it was <0.05. Scientific calculator (CS-82TL) was used for competitive fitness parameters calculations. Results: We performed 24 competitive cultures and 10 individual cultures. In individual cultures, strains' generation number was for Beijing (WT: 4.60 and mutant MR: 4.40), T1 (WT: 2.69 and MR: 2.37), and H37Rv: 2.91. Generation number of WT strains was less than those of MDR strains in both individual and competitive culture. Relative competitive fitness was below 1 (W<1) in 83.3%. Conclusion: MDR strains were less competitive than WT strains in 83.3% of cases. Resistant mutation impacts bacteria fitness.