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1.
Lancet Infect Dis ; 24(2): e106-e112, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37778362

RESUMEN

Next-generation sequencing (NGS) of genomic data has established its fundamental value in public health surveillance, research and development, and precision medicine. In Africa, severe shortages of competent experts in genomics and bioinformatics, few opportunities for research, and inadequate genomic infrastructure have had a knock-on effect on the use of NGS technologies for research and public health practice. Several reasons-ranging from poor funding, inadequate infrastructure for training and practice, to brain drain-might partly account for the scarcity of genomics and bioinformatics expertise in the region. In recognition of these shortcomings and the importance of NGS genomic data, which was amplified during the COVID-19 pandemic in mid-2021, the Africa Centres for Disease Control and Prevention (Africa CDC) through the Africa Pathogen Genomics Initiative began building and expanding Africa's workforce in pathogen surveillance. By the end of 2022, the Africa CDC in collaboration with its partners and centres of excellence had trained 413 personnel, mostly from public health institutions, in 53 (96%) of 55 African Union Member States. Although this training has increased genomics, bioinformatics, and genomic epidemiology literacy, and genomic-informed pathogen surveillance, there is still a need for a strategic and sustainable public health workforce development in Africa.


Asunto(s)
Genómica , Pandemias , Humanos , África/epidemiología , Biología Computacional , Recursos Humanos
3.
Afr J Lab Med ; 11(1): 1677, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36337771

RESUMEN

Background: Previous studies in Nigeria have reported the presence of hepatitis B virus (HBV) genotype E and the availability of immune escape mutants. There is a paucity of data on chronic patients on long-term antiviral therapy for HBV infection. Objective: This study assessed HBV genotypes and drug resistance variants among patients with chronic HBV infection receiving tenofovir in Jos, Nigeria. Methods: This cross-sectional study consecutively enrolled 101 patients (51 with HIV/HBV co-infection and 50 with HBV infection only) on antiviral therapy from February 2018 to May 2019 at four hospitals in Jos, Nigeria. DNA quantification of HBV was performed on all samples; 30 samples with detectable viral load were selected for genotyping using Sanger sequencing by targeting the full-length sequences of reverse transcriptase gene of the HBV genome. Phylogenetic analysis was performed with reference sequences from GenBank. Escape mutant and drug resistance analysis were performed using HBV drug resistance interpretation and Geno2pheno. Results: Only 30 (29.7%) of the 101 study participants had detectable HBV DNA. Of these, six (20.0%) isolates were successfully amplified and sequenced. The identified genotype was E, including escape mutations L127R (16.7%) and G145A (16.7%). Conclusion: This study revealed exclusive dominance of genotype E in Nigeria. The S gene mutations G145A and L271R are known to be associated with modified antigenicity and impaired serologic assays, which may cause false negatives in the detection of anti-HBV surface antigen. The presence of mutants that are associated with vaccine immune escape may also have diagnostic and vaccine immune response implications.

4.
Front Reprod Health ; 4: 887736, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36303664

RESUMEN

Background: Genital human papillomavirus (HPV) is the most common sexually transmitted virus in most populations globally. Adolescent girls and young women (AGYW) remain a key population group at risk for HPV infection. However, the risk factors of HPV infection among AGYW, especially in sub-Saharan Africa, are a subject of little investigation in published literature. Here, we investigated the factors associated with HPV infection among unvaccinated South African AGYW with a high HPV burden (prevalence: 76.1%). Methods: We retrospectively recruited 213 AGYW learners (aged 15-25 years) from a previous cross-sectional study, the HPV Education Intervention Study, conducted in the Eastern Cape, South Africa. Sexually transmitted infections (STIs), bacterial pathobionts, genital ulcers (due to infectious causes), candidiasis, and bacterial vaginosis (BV) in the self-collected vaginal specimens were determined using the Allplex™ Panel Assays. Statistical analyses were performed using STATA v16.1. Continuous and categorical variables were computed by t-test /Wilcoxon rank-sum test and Chi-square/Fisher's exact tests, respectively. Logistic regression was used to determine the univariable predictors of HPV infection. Results: The overall detection rate of any viral STI, bacterial STI, pathobiont, genital ulcer, candidiasis, and BV among the AGYW was 75.0, 34.4, 90.7, 14.4, 26.9, and 43.6%, respectively. The main factors associated with HPV infection were alcohol consumption (p = 0.005), infection with any and multiple Candida species (p = 0.011 and 0.006, respectively), Candida albicans infection (p = 0.010), Ureaplasma urealyticum pathobiont infection (p = 0.044), BV-associated bacteria (specifically Atopobium vaginae: p = 0.039, BV-associated bacteria 2: p = 0.021, Gardnerella vaginalis: p = 0.021, Megasphaera type 1: p = 0.037), and BV (p = 0.011). Conclusions: Our study, albeit not necessarily generalizable, found social behavior as well as specific vaginal microbes as correlates of HPV infection among AGYW in South Africa. There is a need to investigate HPV epidemiology in other AGYW populations. The factors associated with genital HPV infection among AGYW burdened with HPV infection necessitate the need to formulate and implement population-specific public health strategies for creating HPV awareness and reducing its risk.

5.
PLoS One ; 17(8): e0271870, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35939435

RESUMEN

Proteome profile changes post-severe acute respiratory syndrome coronavirus 2 (post-SARS-CoV-2) infection in different body sites of humans remains an active scientific investigation whose solutions stand a chance of providing more information on what constitutes SARS-CoV-2 pathogenesis. While proteomics has been used to understand SARS-CoV-2 pathogenesis, there are limited data about the status of proteome profile in different human body sites infected by the SARS-CoV-2 virus. To bridge this gap, our study aims to characterize the proteins secreted in urine, bronchoalveolar lavage fluid (BALF), gargle solution, and nasopharyngeal samples and assess the proteome differences in these body samples collected from SARS-CoV-2-positive patients. We downloaded publicly available proteomic data from (https://www.ebi.ac.uk/pride/). The data we downloaded had the following identifiers: (i) PXD019423, n = 3 from Charles Tanford Protein Center in Germany. (ii) IPX0002166000, n = 15 from Beijing Proteome Research Centre, China. (iii) IPX0002429000, n = 5 from Huazhong University of Science and Technology, China, and (iv) PXD022889, n = 18 from Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905 USA. MaxQuant was used for the human peptide spectral matching using human and SARS-CoV-2 proteome database which we downloaded from the UniProt database (access date 13th October 2021). The individuals infected with SARS-CoV-2 viruses displayed a different proteome diversity from the different body sites we investigated. Overally, we identified 1809 proteins across the four sample types we compared. Urine and BALF samples had significantly more abundant SARS-CoV-2 proteins than the other body sites we compared. Urine samples had 257(33.7%) unique proteins, followed by nasopharyngeal with 250(32.8%) unique proteins. Gargle solution and BALF had 38(5%) and 73(9.6%) unique proteins respectively. Urine, gargle solution, nasopharyngeal, and bronchoalveolar lavage fluid samples have different protein diversity in individuals infected with SARS-CoV-2. Moreover, our data also demonstrated that a given body site is characterized by a unique set of proteins in SARS-CoV-2 seropositive individuals.


Asunto(s)
COVID-19 , SARS-CoV-2 , Líquido del Lavado Bronquioalveolar , Humanos , Antisépticos Bucales , Proteoma , Proteómica
6.
Microbiol Spectr ; 10(3): e0222921, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35647888

RESUMEN

Bacterial vaginosis (BV) is a common polymicrobial vaginal disorder that is associated with sexually transmitted infections (STIs), including HIV. Several studies have utilized broad-range 16S rRNA gene PCR assays with sequence analysis to characterize cervicovaginal bacterial communities of women with healthy and diseased conditions. With the high burden of BV and STIs among African women, there is a need for targeted PCR assays that can rapidly determine the true epidemiological profile of key cervical microbes, including BV-associated bacteria, and a need to explore the utility of such assays for microbiological diagnosis of BV. Here, we used a taxon-directed 16S rRNA gene quantitative PCR (qPCR) assay to examine the prevalences and determinants of specific cervical microbes among African women with and without HIV infection. Cervical samples were collected using a cytobrush from 162 women (aged ≥30 years) attending a community-based clinic in Eastern Cape, South Africa. The samples were screened for specific microbes (i.e., STIs, emerging sexually transmitted pathogens [pathobionts], and BV-associated bacteria) using a customized bacterial vaginosis microbial DNA qPCR array. Statistical analyses were performed using GraphPad Prism v6.01. Chi-square/Fisher's exact tests were used to evaluate the determinants associated with specific cervical microbes. Only 145 women had any detectable microbes and were included in the analysis. Lactobacillus iners (62.8%) and specific BV-associated bacteria, namely, Gardnerella vaginalis (58.6%), Atopobium vaginae (40.7%), and the pathobiont Ureaplasma parvum (37.9%), were the most prevalent microbes. Hierarchical clustering analysis revealed that 42.8% of the women (62/145) had a diverse array of heterogeneously distributed bacteria typically linked to BV. Women with detectable Lactobacillus species, specifically Lactobacillus crispatus and Lactobacillus jensenii, and to a lesser extent L. iners, had very low prevalence of BV-associated bacteria. Although the cumulative burden of STIs/pathobionts was 62.8%, Chlamydia trachomatis (3.4%), Neisseria gonorrhoeae (4.8%), and Trichomonas vaginalis (4.8%) were detected at low rates. HIV infection was associated with the presence of STIs/pathobionts (P = 0.022) and L. iners (P = 0.003). Prevalent STIs/pathobionts were associated with having multiple partners in the past 12 months (n ≥ 2, P = 0.015), high number of lifetime sexual partners (n ≥ 3, P = 0.007), vaginal sex in the past month (P = 0.010), and decreasing age of women (P = 0.005). C. trachomatis was associated with increasing age among HIV-positive women (P = 0.016). The pathobiont Ureaplasma urealyticum was inversely associated with age of women in the whole cohort (P = 0.018). The overall prevalence of STIs/pathobionts was high and was associated with HIV infection and sexual behavior. Our study helps us to understand the epidemiological trend of STIs and pathobionts and highlights the need to understand the impact of sexual networks on STI and pathobiont transmission and prevention among women in an African setting. IMPORTANCE Bacterial vaginosis (BV), whose etiology remains a matter of controversy, is a common vaginal disorder among reproductive-age women and can increase the risk for sexually transmitted infections (STIs). African women bear a disproportionately high burden of STIs and BV. Using a targeted quantitative PCR (qPCR) assay, a customized bacterial vaginosis microbial DNA qPCR array, we examined the prevalences and determinants of key cervical microbes, including BV-associated bacteria and emerging sexually transmitted pathogens (pathobionts) among women of African descent aged between 30 and 75 years. High-risk behaviors were associated with a higher prevalence of STIs/pathobionts, suggesting the need to better understand the influence of sexual networks on STI and pathobiont transmission and prevention among women. Our molecular assay is important in the surveillance of BV-associated bacteria, pathobionts, and STIs as well as diagnostic microbiology of BV. Furthermore, our research contributes to a better understanding of the epidemiology of STIs and pathobionts in Africa.


Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Vaginosis Bacteriana , Adulto , Anciano , Chlamydia trachomatis , ADN , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Enfermedades de Transmisión Sexual/complicaciones , Enfermedades de Transmisión Sexual/epidemiología , Sudáfrica/epidemiología , Vagina/microbiología , Vaginosis Bacteriana/diagnóstico , Vaginosis Bacteriana/epidemiología , Vaginosis Bacteriana/microbiología
7.
Pan Afr Med J ; 40: 58, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34795837

RESUMEN

INTRODUCTION: Marsdenia macrantha is a crucial source of traditional medicine in Northern Namibia. Its roots are used to treat various health conditions ranging from mouth infections to urinary retention. Despite its medicinal application, there is no known knowledge of its therapeutic properties. Thus, we investigated the phytochemical content and antibacterial activity of M. macrantha. METHODS: M. macrantha root extracts were obtained using three different solvents (distilled water, methanol and acetone) - in the soxhlet and maceration extraction methods. Total phytochemical (terpenoid, alkaloid and/or flavonoid) content was determined by spectrophotometry. Antibacterial activity against common foodborne pathogens (Staphylococcus aureus, Escherichia coli and Salmonella typhi) was determined by both well and disc diffusion method. RESULTS: we detected the presence of all the tested phytochemicals. Methanol gave the highest percentage yield of extraction (mean: 13.95 ± standard deviation: 0.41%) followed by water (10.92 ± 0.11%) and acetone (6.85 ± 0.23%), F-ratio=326.71 and p<0.0003. The total content determined showed that M. macrantha root extract contained more flavonoids than alkaloids (mg of standard per grams of the dry material). Antibacterial analyses showed inhibitory activity against all the selected pathogens, with the highest inhibition zone against S. typhi (19.7 ± 0.3 mm) - for the acetone-prepared root extract. There were variations in minimum inhibitory concentrations of the extracts prepared by the different solvents. CONCLUSION: this is the first study demonstrating the presence of phytochemicals and antibacterial properties of M. macrantha roots. Further studies are needed to isolate and characterize the phytochemicals for antibacterial application.


Asunto(s)
Antibacterianos/farmacología , Marsdenia/química , Extractos Vegetales/farmacología , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Antibacterianos/aislamiento & purificación , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/efectos de los fármacos , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Pruebas de Sensibilidad Microbiana , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Extractos Vegetales/química , Raíces de Plantas , Salmonella typhi/efectos de los fármacos , Solventes/química , Staphylococcus aureus/efectos de los fármacos , Terpenos/aislamiento & purificación , Terpenos/farmacología
8.
Front Immunol ; 12: 730986, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594336

RESUMEN

The standard treatment for bacterial vaginosis (BV) with oral metronidazole is often ineffective, and recurrence rates are high among African women. BV-associated anaerobes are closely associated with genital inflammation and HIV risk, which underscores the importance of understanding the interplay between vaginal microbiota and genital inflammation in response to treatment. In this cohort study, we therefore investigated the effects of metronidazole treatment on the vaginal microbiota and genital cytokines among symptomatic South African women with BV [defined as Nugent score (NS) ≥4] using 16S rRNA gene sequencing and multiplex bead arrays. Among 56 BV-positive women, we observed short-term BV clearance (NS <4) in a proportion of women six weeks after metronidazole treatment, with more than half of these experiencing recurrence by 12 weeks post-treatment. BV treatment temporarily reduced the relative abundance of BV-associated anaerobes (particularly Gardnerella vaginalis and Atopobium vaginae) and increased lactobacilli species (mainly L. iners), resulting in significantly altered mucosal immune milieu over time. In a linear mixed model, the median concentrations of pro-inflammatory cytokines and chemokines were significantly reduced in women who cleared BV compared to pre-treatment. BV persistence and recurrence were strongly associated with mucosal cytokine profiles that may increase the risk of HIV acquisition. Concentrations of these cytokines were differentially regulated by changes in the relative abundance of BVAB1 and G. vaginalis. We conclude that metronidazole for the treatment of BV induced short-term shifts in the vaginal microbiota and mucosal cytokines, while treatment failures promoted persistent elevation of pro-inflammatory cytokine concentrations in the genital tract. These data suggest the need to improve clinical management of BV to minimize BV related reproductive risk factors.


Asunto(s)
Antibacterianos/administración & dosificación , Bacterias/efectos de los fármacos , Citocinas/metabolismo , Mediadores de Inflamación/metabolismo , Metronidazol/administración & dosificación , Membrana Mucosa/efectos de los fármacos , Vagina/efectos de los fármacos , Vaginosis Bacteriana/tratamiento farmacológico , Administración Oral , Adulto , Antibacterianos/efectos adversos , Bacterias/inmunología , Bacterias/patogenicidad , Disbiosis , Femenino , Interacciones Huésped-Patógeno , Humanos , Estudios Longitudinales , Metronidazol/efectos adversos , Membrana Mucosa/inmunología , Membrana Mucosa/metabolismo , Membrana Mucosa/microbiología , Estudios Prospectivos , Reinfección , Sudáfrica , Factores de Tiempo , Resultado del Tratamiento , Vagina/inmunología , Vagina/metabolismo , Vagina/microbiología , Vaginosis Bacteriana/diagnóstico , Vaginosis Bacteriana/inmunología , Vaginosis Bacteriana/microbiología , Adulto Joven
9.
PLoS One ; 16(6): e0253218, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34143825

RESUMEN

Mounting evidence suggests that Lactobacillus species may not necessarily be the sine qua non of healthy cervicovaginal microbiota (CVM), especially among reproductive-age African women. A majority of African women have high-diversity non-Lactobacillus-dominated CVM whose bacterial functions remain poorly characterized. Functional profiling of the CVM is vital for investigating human host-microbiota interactions in health and disease. Here, we investigated the functional potential of L. iners-dominated and high-diversity non-Lactobacillus-dominated CVM of 75 African women with and without bacterial vaginosis (BV) and high-risk human papillomavirus (HR-HPV) infection. Functional contents were predicted using PICRUSt. Microbial taxonomic diversity, BV, and HR-HPV infection statuses were correlated with the inferred functional composition of the CVM. Differentially abundant inferred functional categories were identified using linear discriminant analysis (LDA) effect size (LEfSe) (p-value <0.05 and logarithmic LDA score >2.0). Of the 75 women, 56 (74.7%), 35 (46.7%), and 29 (38.7%) had high-diversity non-Lactobacillus-dominated CVM, BV, and HR-HPV infection, respectively. Alpha diversity of the inferred functional contents (as measured by Shannon diversity index) was significantly higher in women with high-diversity non-Lactobacillus-dominated CVM and BV than their respective counterparts (H statistic ≥11.5, q-value <0.001). Ordination of the predicted functional metagenome content (using Bray-Curtis distances) showed that the samples segregated according to the extent of microbial taxonomic diversity and BV (pseudo-F statistic ≥19.6, q-value = 0.001) but not HR-HPV status (pseudo-F statistic = 1.7, q-value = 0.159). LEfSe analysis of the inferred functional categories revealed that transport systems (including ABC transporters) and transcription factors were enriched in high-diversity CVM. Interestingly, transcription factors and sporulation functional categories were uniquely associated with high-diversity CVM, BV, and HR-HPV infection. Our predictive functional analysis reveals features unique to high-diversity CVM, BV and HR-HPV infections. Such features may represent important biomarkers of BV and HR-HPV infection. Our findings require proof-of-concept functional studies to examine the relevance of these potential biomarkers in women's reproductive health and disease.


Asunto(s)
Cuello del Útero/microbiología , Microbiota/fisiología , Infecciones por Papillomavirus/microbiología , Vagina/microbiología , Vaginosis Bacteriana/microbiología , Adolescente , Adulto , Femenino , Humanos , Lactobacillus/aislamiento & purificación , Adulto Joven
10.
Pan Afr Med J ; 38: 196, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33995802

RESUMEN

The onslaught of COVID-19 pandemic has greatly overwhelmed some of the best healthcare systems in the world. Medical practitioners working in hospitals at the epicenters of COVID-19 pandemic have emphasized on the need to manage mildly ill and convalescent COVID-19 patients at home or community facilities rather than at hospitals during a pandemic. In this article, we highlight that a standardized home- and community-based (HCBC) approach for management of COVID-19 patients will be a key component for preparing hospitals in sub-Saharan Africa (SSA) for a potential surge in COVID-19 cases. So far, based on the trajectory of infection, we think that SSA seems to have a window of opportunity, albeit narrowing, for implementing HCBC. However, there are challenges that will need to be addressed in order to implement and maintain HCBC. Successful implementation and maintenance of HCBC in SSA will require international agencies and key donors to work closely with the national governments; providing them with policy, technical, and financial assistance. Home- and community-based care (HCBC) is also important because it can play a role in advocacy, education, training, and health promotion during COVID-19 pandemic. We further underscore the need for a delicate balance between HCBC and hospital-based care (HBC) approach as well as with COVID-19 mitigation and suppression measures in order to reduce the risk of SARS-CoV-2 community transmission and allow optimal continuity of the HBC. We conclude by emphasizing once again that, for countries in SSA to adequately prepare for the worst-case scenario of COVID-19 pandemic in the absence of a cure, policy makers of member states need to act collectively and fast.


Asunto(s)
COVID-19/terapia , Servicios de Salud Comunitaria/organización & administración , Atención a la Salud/organización & administración , Servicios de Atención de Salud a Domicilio/organización & administración , África del Sur del Sahara , Servicios de Salud Comunitaria/normas , Atención a la Salud/normas , Servicios de Atención de Salud a Domicilio/normas , Hospitalización , Humanos
11.
PLoS One ; 15(12): e0243828, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33332397

RESUMEN

Shiga toxin-producing Escherichia coli are foodborne pathogens that are mostly associated with beef products and have been implicated in human illness. E.coli-associated illness range from asymptomatic conditions of mild diarrhoea to haemorrhagic colitis which can progress into life threatening haemolytic uremic syndrome (HUS). Beef from cattle are regarded as the main reservoir of Shiga toxin-producing E. coli (STEC) pathogen. The aim of this study was to assess the level and sources of contamination of raw beef with STEC, and determine the incidences of STEC strains in raw beef from informal and commercial abattoirs in Windhoek, Namibia. A total of 204 raw beef samples, 37 equipment and 29 hand swabs were collected and tested for STEC. The meat samples were first enriched with pre-warmed buffered peptone water, cultured on Tryptone Bile X-Glucuronide and CHROMagar STEC, and then sub-cultured on nutrient agar. The presence of E.coli in the samples was confirmed by using VITEK 2 E.coli identification cards and PCR. The overall prevalence of STEC in the meat samples from both the abattoirs was 41.66% raw beef samples; 5.40% equipment swabs; and none of the hand swabs was STEC positive. From the STEC positive meat samples 29.41% contained one of the major STEC strains. Moreover, 52% of the 25 samples that contained the major STECs were characterised by eae and stx1, 8% characterised by eae and stx2 while 40% were characterised by eae, stx1 and stx2 virulence genes. This study has revealed the necessity for proper training on meat safety (for meat handlers) as well as the development, implementation and maintenance of effective sanitary dressing procedures at abattoirs to eliminate beef contamination by STECs thereby ensuring the production of wholesome meat, and to prevent the occurrences of STEC infections.


Asunto(s)
Mataderos , Carne Roja/microbiología , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Animales , Bovinos , Contaminación de Alimentos , Genes Bacterianos , Escherichia coli Shiga-Toxigénica/genética , Escherichia coli Shiga-Toxigénica/crecimiento & desarrollo , Virulencia/genética
12.
Front Med (Lausanne) ; 7: 383, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32850898

RESUMEN

While the human microbiota especially that of the gut, cervix, and vagina continue to receive great attention, very little is currently known about the penile (glans, coronal sulcus, foreskin, and shaft) microbiota. The best evidences to date for the potential role of the penile microbiota in human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs) acquisition have come from studies examining medical male circumcision. We are still at the foothills of identifying specific penile bacteria that could be associated with increased risk of STI/HIV acquisition. In this review, we summarize the available literature on the human penile microbiota and how it is impacted by circumcision. We also discuss the potential role of penile microbiota in STIs and its impact on cervicovaginal microbiota. Taken together, the findings from the penile microbiota studies coupled with observational studies on the effect of male circumcision for reduction of STI/HIV infection risk suggest that specific penile anaerobic bacteria such as Prevotella spp. potentially have a mechanistic role that increases the risk of genital infections and syndromes, including bacterial vaginosis in sexual partners. Although penile Corynebacterium and Staphylococcus have been associated with healthy cervicovaginal microbiota and have been found to increase following male circumcision, further investigations are warranted to ascertain the exact roles of these bacteria in the reproductive health of men and women. This review aims to address existing gaps and challenges and future prospects in the penile microbiota research. The information described here may have translational significance, thereby improving reproductive health and management of STI/HIV.

13.
BMC Microbiol ; 20(1): 78, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32252632

RESUMEN

BACKGROUND: To date, the microbiota of the human penis has been studied mostly in connection with circumcision, HIV risk and female partner bacterial vaginosis (BV). These studies have shown that male circumcision reduces penile anaerobic bacteria, that greater abundance of penile anaerobic bacteria is correlated with increased cytokine levels and greater risk of HIV infection, and that the penile microbiota is an important harbour for BV-associated bacteria. While circumcision has been shown to significantly reduce the risk of acquiring human papillomavirus (HPV) infection, the relationship of the penile microbiota with HPV is still unknown. In this study, we examined the penile microbiota of HPV-infected men as well as the impact of HIV status. RESULTS: The penile skin microbiota of 238 men from Cape Town (South Africa) were profiled using Illumina sequencing of the V3-V4 hypervariable regions of the 16S rRNA gene. Corynebacterium and Prevotella were found to be the most abundant genera. Six distinct community state types (CSTs) were identified. CST-1, dominated by Corynebacterium, corresponded to less infections with high-risk HPV (HR-HPV) relative to CSTs 2-6. Men in CST-5 had greater relative abundances of Prevotella, Clostridiales, and Porphyromonas and a lower relative abundance of Corynebacterium. Moreover, they were significantly more likely to have HPV or HR-HPV infections than men in CST-1. Using a machine learning approach, we identified greater relative abundances of the anaerobic BV-associated bacteria (Prevotella, Peptinophilus, and Dialister) and lower relative abundance of Corynebacterium in HR-HPV-infected men compared to HR-HPV-uninfected men. No association was observed between HIV and CST, although the penile microbiota of HIV-infected men had greater relative abundances of Staphylococcus compared to HIV-uninfected men. CONCLUSIONS: We found significant differences in the penile microbiota composition of men with and without HPV and HIV infections. HIV and HR-HPV infections were strongly associated with greater relative abundances of Staphylococcus and BV-associated bacterial taxa (notably Prevotella, Peptinophilus and Dialister), respectively. It is possible that these taxa could increase susceptibility to HIV and HR-HPV acquisition, in addition to creating conditions in which infections persist. Further longitudinal studies are required to establish causal relationships and to determine the extent of the effect.


Asunto(s)
Bacterias/clasificación , Infecciones por VIH/epidemiología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Infecciones por Papillomavirus/epidemiología , Pene/microbiología , Adulto , Bacterias/genética , Bacterias/aislamiento & purificación , Circuncisión Masculina/efectos adversos , Estudios Transversales , ADN Ribosómico/genética , Infecciones por VIH/microbiología , Humanos , Estudios Longitudinales , Aprendizaje Automático , Masculino , Microbiota , Infecciones por Papillomavirus/microbiología , Filogenia , ARN Ribosómico 16S/genética , Estudios Retrospectivos , Análisis de Secuencia de ADN , Sudáfrica
14.
PeerJ ; 7: e7488, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31435492

RESUMEN

BACKGROUND: Lactobacillus spp. are common bacteria in the cervical and vaginal microbiota (CVM) and are thought to represent a "healthy" cervicovaginal state. Several studies have found an independent association between ethnicity/race and cervical and vaginal microbiota (CVM) composition. Women of sub-Saharan African descent appear to be significantly more likely to have non-Lactobacillus-dominated CVM compared to women of European descent. The factors contributing to these differences remain to be fully elucidated. The CVM of Black South African women and factors influencing their CVM remain understudied. In this study, we characterized the cervical microbiota of reproductive-age South African women and assessed the associations of these microbiota with participants' metadata. METHODS: The cervical microbiota from cervical DNA of 62 reproductive-age women were profiled by Ion Torrent sequencing the V4 hypervariable region of the bacterial 16S ribosomal RNA (rRNA) gene and analyzed with the Quantitative Insights Into Microbial Ecology (QIIME), UPARSE, and metagenomeSeq tools. Associations between cervical microbiota and participants' metadata were assessed using GraphPad Prism, R packages and an in-house script. RESULTS: The cervical microbiota clustered into three distinct community state types (CSTs): Lactobacillus iners-dominated cervical microbiota (CST I (38.7%, 24/62)), unclassified Lactobacillus-dominated cervical microbiota (CST II (4.8%, 3/62)), and diverse cervical microbiota (CST III (56.5%, 35/62)) with an array of heterogeneous bacteria, predominantly the bacterial vaginosis (BV)-associated Gardnerella, Prevotella, Sneathia, and Shuttleworthia. CST III was associated with BV (p = 0.001). Women in CST I were more likely to be on hormonal contraception, especially progestin-based, compared to women in CST III (odds ratio: 5.2 (95% CI [1.6-17.2]); p = 0.005). Women on hormonal contraception had a significantly lower alpha (Shannon indices: 0.9 (0.2-1.9) versus 2.3 (0.6-2.3); p = 0.025) and beta (permutational multivariate analysis of variance (PERMANOVA) pseudo-F statistic =4.31, p = 0.019) diversity compared to non-users. There was no significant difference in the alpha (Shannon indices: 1.0 (0.3-2.2) versus 1.9 (0.3-2.2); p = 0.483) and beta (PERMANOVA pseudo-F statistic = 0.89, p = 0.373) diversity in women with versus without human papillomavirus infection. CONCLUSIONS: The majority of Black women in our study had non-Lactobacillus-dominated cervical microbiota. Additional studies are needed to examine whether such microbiota represent abnormal, intermediate or variant states of health. Lastly, the association of hormonal contraception with L. iners dominance requires further in-depth research to confirm this association, determine its biological mechanism and whether it has a beneficial effect on the cervicovaginal health.

15.
BMC Genomics ; 20(1): 368, 2019 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-31088349

RESUMEN

BACKGROUND: Human papillomaviruses (HPVs) are genetically diverse, belonging to five distinct genera: Alpha, Beta, Gamma, Mu and Nu. All papillomaviruses have double stranded DNA genomes that are thought to evolve slowly because they co-opt high-fidelity host cellular DNA polymerases for their replication. Despite extensive efforts to catalogue all the HPV species that infect humans, it is likely that many still remain undiscovered. Here we use the sequences of ten novel Gammapapillomaviruses (Gamma-PVs) characterized in previous studies and related HPVs to analyse the evolutionary dynamics of these viruses at the whole genome and individual gene scales. RESULTS: We found statistically significant incongruences between the phylogenetic trees of different genes which imply gene-to-gene variation in the evolutionary processes underlying the diversification of Gamma-PVs. We were, however, only able to detect convincing evidence of a single recombination event which, on its own, cannot explain the observed incongruences between gene phylogenies. The divergence times of the last common ancestor (LCA) of the Alpha, Beta, Mu, Nu and Gamma genera was predicted to have existed between 49.7-58.5 million years ago, before splitting into the five main lineages. The LCA of the Gamma-PVs at this time was predicted to have existed between 45.3 and 67.5 million years ago: approximately at the time when the simian and tarsier lineages of the primates diverged. CONCLUSION: Consequently, we report here phylogenetic tree incongruence without strong evidence of recombination.


Asunto(s)
ADN Viral/análisis , Gammapapillomavirus/clasificación , Análisis de Secuencia de ADN/métodos , Animales , Evolución Molecular , Gammapapillomavirus/genética , Genoma Viral , Humanos , Filogenia , Recombinación Genética
16.
Papillomavirus Res ; 7: 154-163, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30986570

RESUMEN

In this study we examined potential associations of HPV infection with the cervical microbiota. Cervical samples were collected from 87 HIV-seronegative reproductive-age Black South African women. Microbiota were characterized by Illumina sequencing of the V3-V4 hypervariable regions of the bacterial 16S rRNA gene. Thirty seven (42.5%) and 30 (34.5%) of the women had prevalent HPV and high-risk (HR)-HPV, respectively. Only 23 women (26.4%) had cervical microbiota dominated by a single Lactobacillus species (L. crispatus (2/87 (2.3%)), L. jensenii (2/87 (2.3%)), and L. iners (19/87 (21.8%)). The majority of the women (56/87 (64.4%)) had diverse cervical microbiota consisting of mainly bacterial vaginosis-associated bacteria. The remaining women (8/87 (9.2%)) had microbiota dominated by Aerococcus, Streptococcus, Chlamydia or Corynebacterium. Women with HR-HPV had significantly higher relative abundances of Aerococcaceae, Pseudomonadaceae and Bifidobacteriaceae compared to those with low-risk (LR)-HPV or no HPV-infection (LDA score >2.0, p < 0.05, q < 0.2). Gardnerella, Sneathia, and Atopobium were also found at greater relative abundances in HR-HPV-infected women compared to those with low-risk (LR)-HPV or no HPV-infection (LDA score >2.0, p < 0.05), although the difference was not significant after FDR-adjustment (q > 0.2). Further investigations of the bacterial taxa significantly enriched in HR-HPV-infected women are warranted.


Asunto(s)
Bacterias/clasificación , Bacterias/genética , Cuello del Útero/microbiología , Microbiota , Infecciones por Papillomavirus , Adolescente , Adulto , Población Negra , Análisis por Conglomerados , Estudios Transversales , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sudáfrica , Adulto Joven
17.
Microbiome ; 6(1): 218, 2018 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-30522523

RESUMEN

BACKGROUND: The oral cavity comprises a rich and diverse microbiome, which plays important roles in health and disease. Previous studies have mostly focused on adult populations or in very young children, whereas the adolescent oral microbiome remains poorly studied. Here, we used a citizen science approach and 16S profiling to assess the oral microbiome of 1500 adolescents around Spain and its relationships with lifestyle, diet, hygiene, and socioeconomic and environmental parameters. RESULTS: Our results provide a detailed snapshot of the adolescent oral microbiome and how it varies with lifestyle and other factors. In addition to hygiene and dietary habits, we found that the composition of tap water was related to important changes in the abundance of several bacterial genera. This points to an important role of drinking water in shaping the oral microbiota, which has been so far poorly explored. Overall, the microbiome samples of our study can be clustered into two broad compositional patterns (stomatotypes), driven mostly by Neisseria and Prevotella, respectively. These patterns show striking similarities with those found in unrelated populations. CONCLUSIONS: We hypothesize that these stomatotypes represent two possible global optimal equilibria in the oral microbiome that reflect underlying constraints of the human oral niche. As such, they should be found across a variety of geographical regions, lifestyles, and ages.


Asunto(s)
Bacterias/clasificación , Agua Potable/microbiología , Metagenómica/métodos , Boca/microbiología , Adolescente , Adulto , Bacterias/genética , Bacterias/aislamiento & purificación , ADN Bacteriano/genética , ADN Ribosómico/genética , Conducta Alimentaria , Humanos , Higiene , Estilo de Vida , Neisseria/clasificación , Neisseria/genética , Neisseria/aislamiento & purificación , Filogenia , Prevotella/clasificación , Prevotella/genética , Prevotella/aislamiento & purificación , ARN Ribosómico 16S/genética , Maestros , Análisis de Secuencia de ADN , España
18.
PLoS One ; 12(2): e0171124, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28178281

RESUMEN

HIV-1 transmitted drug resistance (TDR) is of increasing public health concern in sub-Saharan Africa with the rollout of antiretroviral (ARV) therapy. Such data are, however, limited in Kenya, where HIV-1 drug resistance testing is not routinely performed. From a population-based household survey conducted between September and November 2012 in rural western Kenya, we retrospectively assessed HIV-1 TDR baseline rates, its determinants, and genetic diversity among drug-naïve persons aged 15-59 years with acute HIV-1 infections (AHI) and recent HIV-1 infections (RHI) as determined by nucleic acid amplification test and both Limiting Antigen and BioRad avidity immunoassays, respectively. HIV-1 pol sequences were scored for drug resistance mutations using Stanford HIVdb and WHO 2009 mutation guidelines. HIV-1 subtyping was computed in MEGA6. Eighty seven (93.5%) of the eligible samples were successfully sequenced. Of these, 8 had at least one TDR mutation, resulting in a TDR prevalence of 9.2% (95% CI 4.7-17.1). No TDR was observed among persons with AHI (n = 7). TDR prevalence was 4.6% (95% CI 1.8-11.2) for nucleoside reverse transcriptase inhibitors (NRTIs), 6.9% (95% CI 3.2-14.2) for non- nucleoside reverse transcriptase inhibitors (NNRTIs), and 1.2% (95% CI 0.2-6.2) for protease inhibitors. Three (3.4% 95% CI 0.8-10.1) persons had dual-class NRTI/NNRTI resistance. Predominant TDR mutations in the reverse transcriptase included K103N/S (4.6%) and M184V (2.3%); only M46I/L (1.1%) occurred in the protease. All the eight persons were predicted to have different grades of resistance to the ARV regimens, ranging from potential low-level to high-level resistance. HIV-1 subtype distribution was heterogeneous: A (57.5%), C (6.9%), D (21.8%), G (2.3%), and circulating recombinant forms (11.5%). Only low CD4 count was associated with TDR (p = 0.0145). Our findings warrant the need for enhanced HIV-1 TDR monitoring in order to inform on population-based therapeutic guidelines and public health interventions.


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética , Adolescente , Adulto , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , VIH-1/clasificación , Humanos , Kenia/epidemiología , Persona de Mediana Edad , Mutación , Filogenia , Vigilancia de la Población , Prevalencia , Factores de Riesgo , Carga Viral , Adulto Joven
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