24 research outputs found
J Infect Dis
No full textRollout of meningococcal serogroup A conjugate vaccine in Africa started in 2010, aiming to eliminate meningitis outbreaks, in meningitis belt countries. Since then, studies have been conducted, primarily using isolates, to assess the vaccine impact on the distribution of meningococcal strains in the region. Here, we implemented an innovative, culture-free whole-genome sequencing approach on almost 400 clinical specimens collected between 2017 and 2019 from meningococcal meningitis cases in 6 African countries. About 50% of specimens provided high-quality whole-genome sequence data for comprehensive molecular profiling of the meningococcal pathogen. Three major clonal complexes were identified: CC11 associated with serogroup W, CC181 associated with serogroup X, and CC10217 associated with serogroup C, which continues to rise as a predominant clonal complex in the region. Genomic surveillance for meningococcal meningitis can be significantly improved using culture-free methods to increase data representativeness and monitor changes in epidemiological landscape, especially for countries with low culture rate.CC999999/ImCDC/Intramural CDC HHSUnited States/CC/CDC HHSUnited States
In vitro anti-inflammatory and antimicrobial activity of Securidaca longepedunculata and Annona senegalensis hydro-alcoholic extract
No full textAnnona senegalensis and Securidaca longepedunculata are two plants traditionnaly used in inflammation and wounds infection treatment after snakebites.
This study aims to investigate the in vitro anti-inflammatory and antimicrobial activities of the hydroalcoholic extracts of Annona senegalensis and Securidaca longepedunculata.
Antimicrobial activity of the two plant extracts was examined against five bacterial strains with the well diffusion method and the inhibition zones diameters (IZD), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the 96-well microplate dilution method. While antiinflammatory activity was assessed by the albumin denaturation method.
The results obtained showed that the hydroalcoholic extract of Annona senegalensis has antimicrobial property against Staphylococcus aureus (IZD=12.22 ± 0.24 mm, MIC=62.5 mg/mL, MBC=125 mg/mL) and against Pseudomonas aeruginosa (IZD=12.06 ± 0.06 mm, MIC=125 mg/mL, MBC=250 mg/mL). Securidaca longepedunculata also showed its antimicrobial activity against Staphylococcus aureus (IZD=12.03 ± 0.03 mm, MIC=125 mg/mL, MBC=250 mg/mL) and Candida albicans (IZD=12.12 ± 0.07 mm, MIC=62.5 mg/mL, MFC=125 mg/mL).
In the order hand, Annona senegalensis and Securidaca longepedunculata exhibited concentration-dependent anti-inflammatory activity by reducing significantly (p<0.001) the denaturation of BSA. In addition S. longepedunculata inhibited haemolysis significantly (p<0.001) more than Diclofenac sodium at 200 and 400 µg/mL.
Hence, it was concluded that Annona senegalensis and Securidaca longepedunculata possessed anti-inflammatory and antimicrobial properties and can be used in the treatment of inflammation and wounds infection after snakebites.
Keywords: Annona senegalensis, Securidaca longepedunculata, anti-inflammatory, antimicrobial, BSA
Evaluation In Vitro De L’activité Antimicrobienne Des Extraits De Cassia Alata Linn. (Fabaceae)
No full textCassia alata (Linn) is a Togolese flora plant traditionally used in the treatment of skin diseases and diarrhea. The objective of this work was to evaluate the in vitro antimicrobial activity and to highlight certain phytochemical total and fractionated extracts of this plant harvested in southern Togo. These extracts were obtained from polar solvents such as water, ethanol and ethanol / water mixture in equal volume. Microbial strains used consisted of bacteria, Staphylococcus aureus, Escherichia coli and Klebsiella oxytoca and yeasts, Candida albicans and Candida krusei. The antimicrobial activity was evaluated by the liquid medium dilution method coupled to spread on solid medium. Highlighting chemical groups was made by a brief qualitative phytochemical analysis from staining tests. The results show that the ethanol leaves crude extract (EBE) was the most active of all the tested microbial strains. This extract completely inhibited the growth of S. aureus (MIC = 1.25mg/ ml.); very strongly C. albicans (PI = 94.34 % ) and C. krusei (PI = 90.67% ) and strongly E. coli ( PI = 80%) and K. oxytoca (PI=79.14 %). The other extracts were active in some organisms with percentage inhibition (PI) of between 68 and 97 %. The phytochemical screening of some extracts revealed the presence of flavonoïdes, tannins and saponins. C. alata seems to contain compounds that interact to inhibit the growth of yeasts and bacteria. These results in part to justify the use of this plant in the Togolese traditional medicines
Phytochemical Screening, Antimicrobial and Antioxidant Activities of Aloe buettneri, Mitracarpus scaber and Hannoa undulata used in Togolese Cosmetopoeia
No full textBackground: Aloe buettneri, Mitracarpus scaber and Hannoa undulata are three plants species used in the Togolese traditional medicine to cure dermatosis. This study aims at assessing their anti-oxidant and anti-microbial activities on acne-developing micro-organisms.
Methods: Six micro-organisms including Cutibacterium acnes ATCC 6919, Pseudomonas aeruginosa ATCC 27853; Escherichia coli ATCC 25922; Klebsiella pneumoniae ATCC 700603; Staphylococcus aureus ATCC 29213; and Candida albicans ATCC 35659 were used. Inhibition diameter was assessed using the agar well diffusion method. Minimum inhibitory and minimum microbicidal concentrations have been achieved through the liquid dilution method. Anti-oxidant activities were evaluated by DPPH antiradical scaving and FRAP methods. Phytochemical screening was also realized.
Results: All the microorganism’s strains tested, excepted Candida albicans and Escherichia coli, were susceptible to plants extracts at 250 mg/mL in the agar well diffusion assay with inhibition diameters ranging from 12.10 ± 0.07 to 18.20 ± 0.10 mm. The MICs values were comprised between 15.625 mg/mL and 62.5 mg/mL, when MMCs ranged from 31.25 to 125 mg/mL. At the concentration of 500 µg/mL, the scavenging properties on DPPH radicals were 49.20 ± 0.15% for H. undulata, 41.29 ± 0.51% for A. buettneri, 59.57 ± 0.41% for M. scaber and 87.22 ± 0.03% for Quercetin. For FRAP assay, the effective concentration (EC50) of A. buettneri, M. scaber and H. undulata extracts were 977.44 ± 1.13 µg/mL; 267.74 ± 10.13 µg/mL and, 272.54 ± 12.87 µg/mL respectively while quercetin presented the EC50 of 48.63 ± 2.00 µg/mL. The antimicrobial and antioxidant activities of these species might be required to the presence of polyphenols, tannins, flavonoids, triterpenes, saponoside and alkaloids identified by phytochemical screening.
Conclusion: The three plants extracts are all potential natural antimicrobial and antioxidant candidates for treating acne vulgaris.
Keywords: Aloe buettneri, Mitracarpus scaber, Hannoa undulata, antimicrobial activity, antioxidant activity, phytochemical screening, Acne vulgari
J Infect Dis
No full textBackground:The MenAfriNet Consortium supports strategic implementation of case-based meningitis surveillance in key high-risk countries of the African meningitis belt: Burkina Faso, Chad, Mali, Niger, and Togo. We describe bacterial meningitis epidemiology in these 5 countries in 2015\u20132017.Methods:Case-based meningitis surveillance collects case-level demographic and clinical information and cerebrospinal fluid (CSF) laboratory results. Neisseria meningitidis (Nm), Streptococcus pneumoniae (Sp), or Haemophilus influenzae (Hi) cases were confirmed and Nm/Hi were serogrouped/serotyped by real-time PCR, culture, or latex agglutination. We calculated annual incidence in participating districts in each country in cases/100,000 population.Results:From 2015\u20132017, 18,262 suspected meningitis cases were reported; 92% had a CSF specimen available, of which 26% were confirmed as Nm (n=2,433; 56%), Sp (n=1,758; 40%), or Hi (n=180; 4%). Average annual incidences for Nm, Sp, and Hi, respectively, were 7.5, 2.5, and 0.3. Nm incidence was 1.5 in Burkina Faso, 2.7 in Chad, 0.4 in Mali, 14.7 in Niger, and 12.5 in Togo. Several outbreaks occurred: NmC in Niger in 2015\u20132017, NmC in Mali in 2016, and NmW in Togo in 2016\u20132017. Of Nm cases, 53% were NmC, 30% NmW, and 13% NmX. Five NmA cases were reported (Burkina Faso, 2015). NmX increased from 0.6% of Nm cases in 2015 to 27% in 2017.Conclusions:Though bacterial meningitis epidemiology varied widely by country, NmC and NmW caused several outbreaks, NmX increased though was not associated with outbreaks, and overall NmA incidence remained low. An effective low-cost multivalent meningococcal conjugate vaccine could help further control meningococcal meningitis in the region.001/WHO_/World Health OrganizationInternational/CC999999/ImCDC/Intramural CDC HHSUnited States
J Infect Dis
No full textSince 2010, the introduction of an effective serogroup A meningococcal conjugate vaccine has led to the near-elimination of invasive Neisseria meningitidis serogroup A disease in Africa's meningitis belt. However, a significant burden of disease and epidemics due to other bacterial meningitis pathogens remain in the region. High-quality surveillance data with laboratory confirmation is important to monitor circulating bacterial meningitis pathogens and design appropriate interventions, but complete testing of all reported cases is often infeasible. Here, we use case-based surveillance data from 5 countries in the meningitis belt to determine how accurately estimates of the distribution of causative pathogens would represent the true distribution under different laboratory testing strategies. Detailed case-based surveillance data was collected by the MenAfriNet surveillance consortium in up to 3 seasons from participating districts in 5 countries. For each unique country-season pair, we simulated the accuracy of laboratory surveillance by repeatedly drawing subsets of tested cases and calculating the margin of error of the estimated proportion of cases caused by each pathogen (the greatest pathogen-specific absolute error in proportions between the subset and the full set of cases). Across the 12 country-season pairs analyzed, the 95% credible intervals around estimates of the proportion of cases caused by each pathogen had median widths of \ub10.13, \ub10.07, and \ub10.05, respectively, when random samples of 25%, 50%, and 75% of cases were selected for testing. The level of geographic stratification in the sampling process did not meaningfully affect accuracy estimates. These findings can inform testing thresholds for laboratory surveillance programs in the meningitis belt.001/World Health OrganizationInternational/OPP1084298/Bill and Melinda Gates Foundation/2021-09-01T00:00:00Z34469549PMC84095361056
Additional file 1: of Distribution of quinolone resistance gene (qnr) in ESBL-producing Escherichia coli and Klebsiella spp. in LomĂŠ, Togo
No full textAgarose gel electrophoresis (2%) used for the separation of multiplex PCR products. M: molecular size marker (100 bp ladder, Promega, USA); line 1, 8, 9, 12: negative; line 2, 4, 5, 7, 10, 11, 14, 15, 17, 18, 19, 20: qnr B + qnr S genes: line 3: qnr A + qnrB + qnr S genes; line 6: qnrS genes; line 13: qnrB genes; line 21: negative control and line 22: positive control qnrB genes. Qnr A (517 bp), qnrB (469 bp), qnr S (417 bp). (PDF 325 kb
Représentativité et réactivité du système de surveillance de la Fièvre Jaune au Togo, 2004-2014: Representativeness and responsiveness of the Yellow Fever surveillance system in Togo, 2004-2014
No full textIntroduction: Peu d’informations sont disponibles sur le système de surveillance de la fièvre jaune au Togo. L’objectif est d’évaluer la simplicité, la représentativité et la réactivité de ce système. Méthodes: Une étude transversale descriptive a été menée de 2015 à 2016 à l’Institut Na-tional d’Hygiène (INH) qui est le Laboratoire National de Référence (LNR) pour les maladies à po-tentiel épidémique du Togo. La base de données de 2004-2014 de la fièvre jaune- rougeole -rubéole du LNR et le guide de surveillance intégrée des maladies et riposte, le guide d’évaluation des systèmes de surveillance de Centers for Disease Control and Prevention (CDC) ont été utilisés. Les médianes, intervalles interquartiles et les proportions ont été calculés avec Epi Info 7 et Excel 2003. Résultats: Un cas suspect de fièvre jaune nécessite une confirmation biologique qui se fait à plusieurs niveaux. Le système est représentatif de tous les districts, toutes les années et de toutes les populations du Togo. Un total de 3054 de cas suspects a été notifié dont 32 cas probables et 12 cas confirmés, par-mi lesquels, 8 étaient des hommes. Environs 93,01 % (2833) des cas suspects ont été prélevés dans les 14 jours suivants le début des symp-tômes, 28,39% (866) des échantillons ont été acheminés dans les 72 heures et 77,95% des résultats rendus dans les 7 jours rendant le système peu réactif. Conclusion: Le système de surveillance de la fièvre jaune au Togo est représentatif, complexe et peu réactif. Il s’avère nécessaire de mettre en place un système de convoyage rapide des échantillons.
Introduction: Little information is available on yellow fever surveillance system in Togo. The simplicity, representativeness and responsiveness of this system were assessed. Material and Methods: It was a descriptive cross-sectional study conducted from October 2015 to February 2016 at the Institut National d’Hygiène, the National Reference Laboratory (NRL) for epidemic prone diseases of Togo. We used the yellow fever-measles-rubella database, the integrated dis-ease surveillance and response guideline and the Centers for Disease Control and Prevention (CDC) guidelines for surveillance system evaluation. Medians, interquartile intervals and proportions were calculated and presented in tables and figures with Excel 2003 and Epi Info 7. Results: A yellow fever case must be confirmed at several reference levels making yellow fever surveillance complex. This surveillance system is representative of all districts, all years and all populations of Togo. A total of 3054 suspected cases were reported, including 32 probable cases and 12 confirmed cases. Of the confirmed cases, 08 were men. About 93.01% (2833) of the suspected cases samples were taken within 14 days after the symptoms onset, 28,39% (866) of samples were transported within 72 hours and 77, 95% of the results were available within 7 days, making the system unresponsive. Conclusion: The yellow fever surveillance system in Togo is representative, complex, and unresponsive due to the long delay in transporting samples to the NRL. A rapid sample conveying system is recommende
Relationship between Distinct African Cholera Epidemics Revealed via MLVA Haplotyping of 337 Vibrio cholerae Isolates.
No full textBACKGROUND: Since cholera appeared in Africa during the 1970s, cases have been reported on the continent every year. In Sub-Saharan Africa, cholera outbreaks primarily cluster at certain hotspots including the African Great Lakes Region and West Africa. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we applied MLVA (Multi-Locus Variable Number Tandem Repeat Analysis) typing of 337 Vibrio cholerae isolates from recent cholera epidemics in the Democratic Republic of the Congo (DRC), Zambia, Guinea and Togo. We aimed to assess the relationship between outbreaks. Applying this method, we identified 89 unique MLVA haplotypes across our isolate collection. MLVA typing revealed the short-term divergence and microevolution of these Vibrio cholerae populations to provide insight into the dynamics of cholera outbreaks in each country. Our analyses also revealed strong geographical clustering. Isolates from the African Great Lakes Region (DRC and Zambia) formed a closely related group, while West African isolates (Togo and Guinea) constituted a separate cluster. At a country-level scale our analyses revealed several distinct MLVA groups, most notably DRC 2011/2012, DRC 2009, Zambia 2012 and Guinea 2012. We also found that certain MLVA types collected in the DRC persisted in the country for several years, occasionally giving rise to expansive epidemics. Finally, we found that the six environmental isolates in our panel were unrelated to the epidemic isolates. CONCLUSIONS/SIGNIFICANCE: To effectively combat the disease, it is critical to understand the mechanisms of cholera emergence and diffusion in a region-specific manner. Overall, these findings demonstrate the relationship between distinct epidemics in West Africa and the African Great Lakes Region. This study also highlights the importance of monitoring and analyzing Vibrio cholerae isolates
Indices of genetic diversity per population.
No full text<p>Genetic diversity (Nei, 1987) per population of the 328 <i>V</i>. <i>cholerae</i> isolates was calculated in GenoDive 2.0b25.</p><p>Indices of genetic diversity per population.</p
