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In recent years, a global increase in the number of reports of human vibriosis involving V. cholerae non-O1/O139 (NOVC) and other Vibrio spp. has been observed. In this context, the Belgian National Reference Center for Vibrio conducted an assessment of the presence of Vibrio spp. in recreational waters. Water sampling was performed monthly in different lakes in Wallonia and Flanders, including the North Sea. The collected water was then filtrated and cultured, and Vibrio spp. was quantified according to the Most Probable Number (MPN). Presumptive colonies were confirmed via MALDI-TOF, and PCR for virulence genes was applied if justified. No Vibrio spp. was found in the analyzed water bodies in Wallonia. However, NOVC was isolated from three different lakes in Flanders and from coastal water. In addition, V. alginolyticus and V. parahaemolyticus were also detected in coastal water. No clear impact of the pH and temperature was observed on Vibrio spp. occurrence. Our study demonstrates the presence of Vibrio spp. in different bathing water bodies, mostly in the north of Belgium, and supports the recommendation to include Vibrio spp. as a water quality indicator for bathing water quality assessment to ensure the safety of water recreational users in Belgium.
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Vibriosis , Vibrio cholerae , Vibrio , Humanos , Bélgica , Estaciones del Año , Vibrio/genética , Vibrio cholerae/genética , Vibriosis/epidemiologíaRESUMEN
PURPOSE: This study aimed to evaluate the performance and ease of use of the Revogene® GBS DS PCR assay for the intrapartum detection of Group B Streptococcus (GBS) colonization, as compared with intrapartum culture and antenatal culture-based screening. METHODS: Between April and August 2019, 398 women who gave birth in one of the three maternities participating in this study agreed to the collection of a vaginal swab when they arrived in the labor ward. The samples were immediately sent to the adjacent laboratory where they were discharged into the buffer provided with the Revogene® GBS DS assay. Part of the buffer was used to perform the Revogene® GBS DS test, and part of the same buffer was used for GBS culture. RESULTS: The Revogene® GBS DS assay provided a valid result in less than 70 min for 356 (89%) women. The sensitivity of the test was 85.7% (66.4-95.3%). The specificity of the test was 99.1% (97.3-99.8%). The positive predictive value was 88.9% (69.7-97.1%). The negative predictive value was 98.9% (96.9-99.6%). CONCLUSION: The easy-to-use Revogene® GBS DS assay provides a valuable tool for the detection of GBS colonization at the beginning of labor. The sensitivity and turn-around time are adequate. The high number of invalid results needs to be addressed before the Revogene® GBS DS test can be expected to replace the current screening-based approach.
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Complicaciones Infecciosas del Embarazo , Infecciones Estreptocócicas , Embarazo , Femenino , Humanos , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Complicaciones Infecciosas del Embarazo/diagnóstico , Diagnóstico Prenatal/métodos , Valor Predictivo de las Pruebas , Streptococcus agalactiae/genética , Infecciones Estreptocócicas/diagnóstico , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Group B streptococcus (GBS) remains a leading cause of invasive disease, mainly sepsis and meningitis, in infants < 3 months of age and of mortality among neonates. This study, a major component of the European DEVANI project (Design of a Vaccine Against Neonatal Infections) describes clinical and important microbiological characteristics of neonatal GBS diseases. It quantifies the rate of antenatal screening and intrapartum antibiotic prophylaxis among cases and identifies risk factors associated with an adverse outcome. METHODS: Clinical and microbiological data from 153 invasive neonatal cases (82 early-onset [EOD], 71 late-onset disease [LOD] cases) were collected in eight European countries from mid-2008 to end-2010. RESULTS: Respiratory distress was the most frequent clinical sign at onset of EOD, while meningitis is found in > 30% of LOD. The study revealed that 59% of mothers of EOD cases had not received antenatal screening, whilst GBS was detected in 48.5% of screened cases. Meningitis was associated with an adverse outcome in LOD cases, while prematurity and the presence of cardiocirculatory symptoms were associated with an adverse outcome in EOD cases. Capsular-polysaccharide type III was the most frequent in both EOD and LOD cases with regional differences in the clonal complex distribution. CONCLUSIONS: Standardizing recommendations related to neonatal GBS disease and increasing compliance might improve clinical care and the prevention of GBS EOD. But even full adherence to antenatal screening would miss a relevant number of EOD cases, thus, the most promising prophylactic approach against GBS EOD and LOD would be a vaccine for maternal immunization.
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Complicaciones Infecciosas del Embarazo , Infecciones Estreptocócicas , Recién Nacido , Lactante , Humanos , Femenino , Embarazo , Streptococcus agalactiae , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/prevención & control , Profilaxis Antibiótica/efectos adversos , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Europa (Continente)/epidemiologíaRESUMEN
While patient groups at risk for severe COVID-19 infections are now well identified, the risk factors associated with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) transmission and immunization are still poorly understood. In a cohort of staff members of a Belgian tertiary academic hospital tested for SARS-CoV-2 antibodies during the early phase of the pandemic and followed-up after 6 weeks, 3 months and 10 months, we collected personal, occupational and medical data, as well as symptoms based on which we constructed a COVID-19 score. Seroprevalence was higher among participants in contact with patients or with COVID-19 confirmed subjects or, to a lesser extent, among those handling respiratory specimens, as well as among participants reporting an immunodeficiency or a previous or active hematological malignancy, and correlated with several symptoms. In multivariate analysis, variables associated with seropositivity were: contact with COVID-19 patients, immunodeficiency, previous or active hematological malignancy, anosmia, cough, nasal symptoms, myalgia, and fever. At 10 months, participants in contact with patients and those with higher initial COVID-19 scores were more likely to have sustained antibodies, whereas those with solid tumors or taking chronic medications were at higher risk to become seronegative.
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COVID-19 , Neoplasias Hematológicas , Anticuerpos Antivirales , COVID-19/epidemiología , Atención a la Salud , Personal de Salud , Humanos , SARS-CoV-2 , Estudios Seroepidemiológicos , UniversidadesRESUMEN
Asymptomatic and pauci-symptomatic cases contribute to underestimating the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Moreover, we have few studies available on the longitudinal follow-up of SARS-CoV-2 antibodies after natural infection. We tested staff members of a Belgian tertiary academic hospital for SARS-CoV-2 IgG, IgM, and IgA antibodies. We analyzed the evolution of IgM and IgG after 6 weeks, and the persistence of IgG after 3 and 10 months. At the first evaluation, 409/3776 (10.8%) participants had a positive SARS-CoV-2 serology. Among initially seropositive participants who completed phases 2 and 3, IgM were still detected after 6 weeks in 53.1% and IgG persisted at 12 weeks in 82.0% (97.5% of those with more than borderline titers). IgG levels were higher and increased over time in symptomatic but were lower and stable in asymptomatic participants. After 10 months, 88.5% of participants had sustained IgG levels (97.0% of those with more than borderline titers).
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COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Atención a la Salud , Humanos , Prevalencia , UniversidadesRESUMEN
Despite the high prevalence of both cervico-vaginal human papillomavirus (HPV) infection and bacterial vaginosis (BV) worldwide, their causal relationship remains unclear. While BV has been presumed to be a risk factor for HPV acquisition and related carcinogenesis for a long time, here, supported by both a large retrospective follow-up study (n = 6,085) and extensive in vivo data using the K14-HPV16 transgenic mouse model, we report a novel blueprint in which the opposite association also exists. Mechanistically, by interacting with several core members (NEMO, CK1 and ß-TrCP) of both NF-κB and Wnt/ß-catenin signaling pathways, we show that HPV E7 oncoprotein greatly inhibits host defense peptide expression. Physiologically secreted by the squamous mucosa lining the lower female genital tract, we demonstrate that some of these latter are fundamental factors governing host-microbial interactions. More specifically, several innate molecules down-regulated in case of HPV infection are hydrolyzed, internalized and used by the predominant Lactobacillus species as amino acid source sustaining their growth/survival. Collectively, this study reveals a new viral immune evasion strategy which, by its persistent/negative impact on lactic acid bacteria, ultimately causes the dysbiosis of vaginal microbiota.
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Microbiota , Infecciones por Papillomavirus , Vaginosis Bacteriana , Aminoácidos , Animales , Femenino , Estudios de Seguimiento , Lactobacillus/fisiología , Ratones , Microbiota/fisiología , Membrana Mucosa , Péptidos , Estudios Retrospectivos , Vagina/microbiología , Vaginosis Bacteriana/microbiologíaRESUMEN
Prevention of perinatal Group B Streptococcus (GBS) transmission is crucial in our effort to prevent Early-onset GBS disease. Here, we established the performance of the Revogene GBS DS assay for the detection of group B streptococcus on intrapartum vaginal samples in a laboratory environment using a prospective noninterventional study design. Intrapartum vaginal swabs were enriched using a selective culture method which served as study reference method. Overall, 119 patients were enrolled with an antenatal and intrapartum Group B Streptococcus colonization prevalence of 12.9% and 11.8%, respectively. Compared to intrapartum culture, the Revogene GBS DS assay had a sensitivity of 92.9% and a specificity of 99.1%, while the antenatal culture displayed a sensitivity 78.6% of and specificity of 96.2%. The Revogene GBS DS assay displayed an acceptable performance according to the European Group B Streptococcus consensus recommendations. Complementary studies in clinical practice are needed to confirm these findings.
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Complicaciones Infecciosas del Embarazo , Infecciones Estreptocócicas , Femenino , Humanos , Tamizaje Masivo , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Estudios Prospectivos , Infecciones Estreptocócicas/diagnóstico , Streptococcus agalactiae/genética , VaginaRESUMEN
Dysbiosis of gut microbiota (GM) has been involved in the pathophysiology of arterial hypertension (HT), via a putative role of short chain fatty acids (SCFAs). Its role in the circadian regulation of blood pressure (BP), also called "the dipping profile", has been poorly investigated. Sixteen male volunteers and 10 female partners were subjected to 24 h ambulatory BP monitoring and were categorized in normotensive (NT) versus HT, as well as in dippers versus non-dippers. Nuclear magnetic resonance (NMR)-based metabolomics was performed on stool samples. A 5-year comparative follow-up of BP profiles and stool metabolomes was done in men. Significant correlations between stool metabolome and 24 h mean BP levels were found in both male and female cohorts and in the entire cohort (R2 = 0.72, R2 = 0.79, and R2 = 0.45, respectively). Multivariate analysis discriminated dippers versus non-dippers in both male and female cohorts and in the entire cohort (Q2 = 0.87, Q2 = 0.98, and Q2 = 0.68, respectively). Fecal amounts of acetate, propionate, and butyrate were higher in HT versus NT patients (p = 0.027; p = 0.015 and p = 0.015, respectively), as well as in non-dippers versus dippers (p = 0.027, p = 0.038, and p = 0.036, respectively) in the entire cohort. SCFA levels were significantly different in patients changing of dipping status over the 5-year follow-up. In conclusion, stool metabolome changes upon global and circadian BP profiles in both genders.
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To assess the incidence, clinical, microbiological features and outcome of invasive Streptococcus agalactiae (GBS) infections in non-pregnant adults in three tertiary hospitals of the Brussels-Capital Region. All bacterial cultures positive for GBS, from 2005 to 2019 from 3 hospitals of the Brussels-Capital Region, were extracted, and only cases of invasive diseases were included. Medical files were retrospectively retrieved for risk factors, clinical manifestations and outcome and also antibiotic-susceptibility testing and GBS serotypes. Incidence rates were calculated based on the hospitals catchment populations. A total of 337 cases of GBS-invasive infections were included. The incidence of invasive GBS for the 3 hospitals increased from 3.7 to 8.2 cases per 100.000 inhabitants between 2009 and 2018 (p = 0.04). The most frequently identified risk factors were diabetes (36.8%), obesity (35.0%), cancer (21.7%), renal disease (20.8%), and advanced age (≥ 65 years; 47.2%). Isolated bacteremia (22%), osteoarticular infection (21.4%), abscesses (13.9%), and skin and soft tissue infections (18.4%) were the most frequent manifestations. Intensive care unit admission was required in 21.7% and overall mortality was 9.4%. All strains remained susceptible to penicillin over the years. Up to 20% of strains were resistant to clindamycin. Serotypes Ia, Ib, II, III, IV, and V represented 96.8% of the available serotypes (60/62). As reported in several countries, invasive GBS disease in non-pregnant adults represents an increasing burden, particularly among diabetic, obese, and elderly patients. Almost all serotypes identified are included in the upcoming hexavalent GBS conjugate vaccine.
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Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Bélgica/epidemiología , Farmacorresistencia Bacteriana , Femenino , Mortalidad Hospitalaria , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Serogrupo , Infecciones Estreptocócicas/epidemiología , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/efectos de los fármacos , Centros de Atención TerciariaRESUMEN
Control of the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic requires accurate laboratory testing to identify infected individuals while also clearing essential staff to continue to work. At the current time, a number of quantitative real-time PCR (qRT-PCR) assays have been developed to identify SARS-CoV-2, targeting multiple positions in the viral genome. While the mutation rate of SARS-CoV-2 is moderate, given the large number of transmission chains, it is prudent to monitor circulating viruses for variants that might compromise these assays. Here, we report the identification of a C-to-U transition at position 26340 of the SARS-CoV-2 genome that is associated with failure of the cobas SARS-CoV-2 E gene qRT-PCR in eight patients. As the cobas SARS-CoV-2 assay targets two positions in the genome, the individuals carrying this variant were still called SARS-CoV-2 positive. Whole-genome sequencing of SARS-CoV-2 showed all to carry closely related viruses. Examination of viral genomes deposited on GISAID showed this mutation has arisen independently at least four times. This work highlights the necessity of monitoring SARS-CoV-2 for the emergence of single-nucleotide polymorphisms that might adversely affect RT-PCRs used in diagnostics. Additionally, it argues that two regions in SARS-CoV-2 should be targeted to avoid false negatives.
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Betacoronavirus/genética , Proteínas del Envoltorio Viral/genética , Betacoronavirus/clasificación , Betacoronavirus/aislamiento & purificación , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Proteínas de la Envoltura de Coronavirus , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Bases de Datos Genéticas , Reacciones Falso Negativas , Genoma Viral/genética , Humanos , Técnicas de Diagnóstico Molecular , Mutación , Filogenia , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2RESUMEN
Introduction: COVID-19 Ag Respi-Strip, an immunochromatographic (ICT) assay for the rapid detection of SARS-CoV-2 antigen on nasopharyngeal specimen, has been developed to identify positive COVID-19 patients allowing prompt clinical and quarantine decisions. In this original research article, we describe the conception, the analytical and clinical performances as well as the risk management of implementing the COVID-19 Ag Respi-Strip in a diagnostic decision algorithm. Materials and Methods: Development of the COVID-19 Ag Respi-Strip resulted in a ready-to-use ICT assay based on a membrane technology with colloidal gold nanoparticles using monoclonal antibodies directed against the SARS-CoV and SARS-CoV-2 highly conserved nucleoprotein antigen. Four hundred observations were recorded for the analytical performance study and thirty tests were analyzed for the cross-reactivity study. The clinical performance study was performed in a retrospective multi-centric evaluation on aliquots of 328 nasopharyngeal samples. COVID-19 Ag Respi-Strip results were compared with qRT-PCR as golden standard for COVID-19 diagnostics. Results: In the analytical performance study, the reproducibility showed a between-observer disagreement of 1.7%, a robustness of 98%, an overall satisfying user friendliness and no cross-reactivity with other virus-infected nasopharyngeal samples. In the clinical performance study performed in three different clinical laboratories during the ascendant phase of the epidemiological curve, we found an overall sensitivity and specificity of 57.6 and 99.5%, respectively with an accuracy of 82.6%. The cut-off of the ICT was found at CT <22. User-friendliness analysis and risk management assessment through Ishikawa diagram demonstrate that COVID-19 Ag Respi-Strip may be implemented in clinical laboratories according to biosafety recommendations. Conclusion: The COVID-19 Ag Respi-Strip represents a promising rapid SARS-CoV-2 antigen assay for the first-line diagnosis of COVID-19 in 15 min at the peak of the pandemic. Its role in the proposed diagnostic algorithm is complementary to the currently-used molecular techniques.
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Gut microbiota may influence blood pressure (BP), namely via end products of carbohydrate fermentation. After informed consent, male volunteers were prospectively categorized into 3 groups upon European Society of Hypertension criteria based on 24-hour ambulatory BP measurements: (1) hypertension, (2) borderline hypertension, and (3) normotension. Stool, urine and serum samples were collected in fasting conditions. Gut microbiota was characterized by 16S amplicon sequencing. Metabolomics, including quantification of short-chain fatty acids, was conducted using nuclear magnetic resonance. Two-way ANOVA combined with Tukey post hoc test, as well as multiple permutation test and Benjamini-Hochberg-Yekutieli false discovery rate procedure, was used. The cohort included 54 males: 38 hypertensive (including 21 under treatment), 7 borderline, and 9 normotensive. No significant difference was observed between groups concerning age, body mass index, smoking habits, and weekly alcohol consumption. The genus Clostridium sensu stricto 1 positively correlated with BP levels in nontreated patients (n=33). This correlation was significant after multiple permutation tests but was not substantiated following false discovery rate adjustment. Short-chain fatty acid levels were significantly different among groups, with higher stool levels of acetate, butyrate, and propionate in hypertensive versus normotensive individuals. No difference was observed in serum and urine metabolomes. Correlation between stool metabolome and 24-hour BP levels was evidenced, with R2 reaching 0.9. Our pilot study based on 24-hour ambulatory BP measurements, 16S amplicon sequencing, and metabolomics supports an association between gut microbiota and BP homeostasis, with changes in stool abundance of short-chain fatty acids.
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Presión Sanguínea/fisiología , Ácidos Grasos Volátiles/análisis , Heces/química , Microbioma Gastrointestinal/fisiología , Hipertensión/fisiopatología , Adulto , Humanos , Hipertensión/microbiología , Masculino , Metaboloma , Persona de Mediana Edad , Proyectos PilotoRESUMEN
Real-time PCR are often used for the diagnosis and monitoring of Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections in susceptible populations. In this context, we evaluated the analytical performances of the Abbott RealTime CMV/EBV maxCycle protocol automated on the m2000 platform (Abbott). It was compared to our routinely-used procedure consisting of a NucleoMag® DNA extraction automated on a STARlet platform followed by manually processed CMV and EBV quantitative real-time PCR (Diagenode). In this study, we showed that both EBV assays exhibited a similar sensitivity but with a better precision for the EBV Abbott RealTime assay. For the CMV performances, the Abbott assay was more sensitive and more precise than our routine method. The use of WHO International Standards also indicated a slight underestimation of the viral loads (-0.25 log10 IU/mL and -0.21 log10 IU/mL for CMV and EBV assays respectively) while these were rather overestimated with the Starlet/Diagenode method (0.48 log10 IU/mL and 0.19 log10 IU/mL for CMV and EBV assays respectively). These trends were confirmed using relevant whole-blood clinical samples and external quality controls. The workflows were also compared and we highlighted a significant technician hands-on time reduction (-63%) using the Abbott CMV/EBV maxCycle automated protocol.
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Sangre/virología , Citomegalovirus/aislamiento & purificación , Herpesvirus Humano 4/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Carga Viral/métodos , Automatización de Laboratorios/métodos , Citomegalovirus/genética , Herpesvirus Humano 4/genética , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Manejo de Especímenes/métodos , Carga Viral/normasRESUMEN
Onychomycosis represents one of the most frequent mycoses in the world. Causative agents are mainly dermatophytes, but yeasts and nondermatophyte moulds can also be involved. Conventional diagnostic methods include direct microscopy (or histology) and culturing. However, molecular methods are becoming increasingly popular in this field. The DermaGenius® (DG) Nail multiplex assay (PathoNostics, The Netherlands) is a new commercial real-time polymerase chain reaction (PCR) kit, which can detect Trichophyton rubrum, Trichophyton interdigitale and Candida albicans directly in nails. The present study is a retrospective evaluation of the kit applied to 138 finger and toenail clippings in comparison to histology and culture methods. The sensitivity and specificity of the PCR assay are 80% (76/95) and 74.4% (32/43), respectively, when histology and culture are used as reference to define onychomycosis. DG performance is not different from histology combined with culture (P = .11) but the best diagnostic efficacy (88.4%, 122/138) is obtained by the combination of histology and DG. In conclusion, this study emphasizes the clinical usefulness of the DG in diagnostics. The high specificity of this test guarantees a better identification compared to culture that can lead to dermatophyte misidentifications. It is a reliable PCR assay that shortens the time to diagnosis and can unmask the presence of nongrowing fungal pathogens in nails.
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Arthrodermataceae/aislamiento & purificación , Candida albicans/aislamiento & purificación , Uñas/microbiología , Onicomicosis/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Arthrodermataceae/genética , Candida albicans/genética , Niño , ADN de Hongos/genética , Femenino , Técnicas Histológicas , Humanos , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Tipificación Micológica , Juego de Reactivos para Diagnóstico , Estudios Retrospectivos , Sensibilidad y Especificidad , Trichophyton/genética , Adulto JovenRESUMEN
The precise impact of the somatotrope axis upon the immune system is still highly debated. We have previously shown that mice with generalized ablation of growth hormone (GH) releasing hormone (GHRH) gene (Ghrh-/-) have normal thymus and T-cell development, but present a marked spleen atrophy and B-cell lymphopenia. Therefore, in this paper we have investigated vaccinal and anti-infectious responses of Ghrh-/- mice against S. pneumoniae, a pathogen carrying T-independent antigens. Ghrh-/- mice were unable to trigger production of specific IgM after vaccination with either native pneumococcal polysaccharides (PPS, PPV23) or protein-PPS conjugate (PCV13). GH supplementation of Ghrh-/- mice restored IgM response to PPV23 vaccine but not to PCV13 suggesting that GH could exert a specific impact on the spleen marginal zone that is strongly implicated in T-independent response against pneumococcal polysaccharides. As expected, after administration of low dose of S. pneumoniae, wild type (WT) completely cleared bacteria after 24 h. In marked contrast, Ghrh-/- mice exhibited a dramatic susceptibility to S. pneumoniae infection with a time-dependent increase in lung bacterial load and a lethal bacteraemia already after 24 h. Lungs of infected Ghrh-/- mice were massively infiltrated by inflammatory macrophages and neutrophils, while lung B cells were markedly decreased. The inflammatory transcripts signature was significantly elevated in Ghrh-/- mice. In this animal model, the somatotrope GHRH/GH/IGF1 axis plays a vital and unsuspected role in vaccine and immunological defense against S. pneumoniae.
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Linfocitos B/inmunología , Hormona Liberadora de Hormona del Crecimiento/inmunología , Hormona del Crecimiento/deficiencia , Vacunas Neumococicas/inmunología , Transducción de Señal/inmunología , Streptococcus pneumoniae/inmunología , Animales , Linfocitos B/patología , Hormona del Crecimiento/inmunología , Hormona Liberadora de Hormona del Crecimiento/genética , Inmunoglobulina M/genética , Inmunoglobulina M/inmunología , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/inmunología , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Noqueados , Transducción de Señal/genéticaRESUMEN
BACKGROUND: Group B streptococcus (GBS) infection is a leading cause of severe neonatal infection. Maternal GBS carriage during pregnancy is the main risk factor for both early-onset and late-onset GBS disease. High incidence of GBS infection has been reported in HIV-exposed but -uninfected infants (HEU). We aimed to determine the prevalence, characteristics, and risk factors for GBS colonization in HIV-infected and HIV-uninfected pregnant women living in Belgium. METHODS: Between January 1, 2011, and December 31, 2013, HIV-infected (n = 125) and -uninfected (n = 120) pregnant women had recto-vaginal swabs at 35-37 weeks of gestation and at delivery for GBS detection. Demographic, obstetrical, and HIV infection-related data were prospectively collected. GBS capsular serotyping was performed on a limited number of samples (33 from HIV-infected and 16 from HIV-uninfected pregnant women). RESULTS: There was no significant difference in the GBS colonization rate between HIV-infected and -uninfected pregnant women (29.6% vs 24.2%, respectively). HIV-infected women were more frequently colonized by serotype III (36.4% vs 12.5%), and the majority of serotype III strains belonged to the hypervirulent clone ST-17. Exclusively trivalent vaccine serotypes (Ia, Ib, and III) were found in 57.6% and 75% of HIV-infected and -uninfected women, respectively, whereas the hexavalent vaccine serotypes (Ia, Ib, II, III, IV, and V) were found in 97% and 100%, respectively. CONCLUSIONS: HIV-infected and -uninfected pregnant women living in Belgium have a similar GBS colonization rate. A trend to a higher colonization rate with serotype III was found in HIV-infected women, and those serotype III strains belong predominantly to the hypervirulent clone ST17.
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Malaria is a major public health problem in the Democratic Republic of Congo. Despite progress achieved over the past decade in the fight against malaria, further efforts have to be done such as in the surveillance and the containment of Plasmodium falciparum resistant strains. We investigated resistance to artemisinin-based combination therapies currently in use in Democratic Republic of Congo by surveying molecular polymorphisms in three genes: pfcrt, pfmdr1 and pfk13 to explore possible emergence of amodiaquine, lumefantrine or artemisinin resistance in Democratic Republic of Congo. This study essentially revealed that resistance to chloroquine is still decreasing while polymorphism related to amodiaquine resistance seems to be not present in Democratic Republic of Congo, that three samples, located in the east of the country, harbor Pfmdr1 amplification and that none of the mutations found in South-East Asia correlated with artemisinine resistance have been found in Democratic Republic of Congo. But new mutations have been identified, especially the M476K, occurred in the same position that the M476I previously identified in the F32-ART strain, strongly resistant to artemisinine. Antimalarial first-line treatments currently in use in Democratic Republic of Congo are not associated with emergence of molecular markers of resistance.
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Artemisininas/uso terapéutico , Resistencia a Medicamentos/genética , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , República Democrática del Congo , Quimioterapia Combinada , Dosificación de Gen , Marcadores Genéticos , Geografía , Haplotipos/genética , Humanos , Mutación/genética , Polimorfismo Genético , Proteínas Protozoarias/genéticaRESUMEN
The World Health Organization estimates that every year, one million neonatal deaths occur because of neonatal infection. Furthermore, an equal number of stillbirths are thought to be caused by infections. Here we discuss the role of Streptococcus agalactiae (group B Streptococcus, GBS) in neonatal disease and stillbirth.
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Membrana Mucosa/microbiología , Mortalidad Perinatal , Complicaciones Infecciosas del Embarazo/microbiología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/patogenicidad , Vagina/microbiología , Femenino , Humanos , Recién Nacido , Embarazo , Complicaciones Infecciosas del Embarazo/mortalidad , Complicaciones Infecciosas del Embarazo/patología , Mortinato , Infecciones Estreptocócicas/patologíaRESUMEN
Group B Streptococcus (GBS) is a major cause of neonatal sepsis and mortality worldwide. Studies from both developed and developing countries have shown that HIV-exposed but uninfected (HEU) infants are at increased risk of infectious morbidity, as compared to HIV-unexposed uninfected infants (HUU). A higher susceptibility to GBS infections has been reported in HEU infants, particularly late-onset diseases and more severe manifestations of GBS diseases. We review here the possible explanations for increased susceptibility to GBS infection. Maternal GBS colonization during pregnancy is a major risk factor for early-onset GBS invasive disease, but colonization rates are not higher in HIV-infected compared to HIV-uninfected pregnant women, while selective colonization with more virulent strains in HIV-infected women is suggested in some studies. Lower serotype-specific GBS maternal antibody transfer and quantitative and qualitative defects of innate immune responses in HEU infants may play a role in the increased risk of GBS invasive disease. The impact of maternal antiretroviral treatment and its consequences on immune activation in HEU newborns are important to study. Maternal immunization presents a promising intervention to reduce GBS burden in the growing HEU population.
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Plasmodiums are protozoa that may infect various hosts. Only five species are now recognized as naturally parasitizing humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale and Plasmodium knowlesi. This fifth species, P. knowlesi, previously identified as naturally parasitizing the monkey Macaca fascicularis, has been microscopically confused for a long time with P. malariae or P. falciparum and it was not possible to correctly differentiate them until the advent of molecular biology. To date, natural human infections with P. knowlesi only occur in Southeast Asia and a similar phenomenon of natural transmission of simian plasmodium to humans has not been reported elsewhere. This study was conducted to investigate a possible transmission of African small monkey's plasmodium to humans in populations living near the rainforest of the Democratic Republic of Congo (DRC) where several species of non-human primates are living. Two successive real-time PCRs were identified in the literature and used in combination for purpose. Only P. falciparum was found in this study. However, studies with larger samples and with more advanced techniques should be conducted.