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Research paper thumbnail of Patients characteristics corresponding to the sequenced strains

<p>Patients characteristics corresponding to the sequenced strains.</p

Research paper thumbnail of HBV DNA detection and HBV DNA VL according to HBV serological profiles

<p>HBV DNA detection and HBV DNA VL according to HBV serological profiles.</p

Research paper thumbnail of Percentage of patients untreated versus treated, and distribution of antiviral HBV therapies

<p>Percentage of patients untreated versus treated, and distribution of antiviral HBV thera... more <p>Percentage of patients untreated versus treated, and distribution of antiviral HBV therapies.</p

Research paper thumbnail of Baseline characteristics and HBsAg prevalence in the studied population

<p>Baseline characteristics and HBsAg prevalence in the studied population.</p

Research paper thumbnail of Distribution of mutations in the Polymerase gene (A) and in S gene (B) using Mutation Reporter Tool (http://hvdr.bioinf.wits.ac.za/tools/)

<p>Letters preceding each locus on the X axis show the reference patterns and the letters i... more <p>Letters preceding each locus on the X axis show the reference patterns and the letters indexed in colors show the mutated patterns. Only detected mutations are represented.</p

Research paper thumbnail of Phylogenetic analysis of partial surface gene (Fig 3A) and core gene (Fig 3B) rooted on HBV woolly monkey strain (AY226578)

<p>This tree was inferred by the Bayesian method in the GTR model. Samples sequenced in thi... more <p>This tree was inferred by the Bayesian method in the GTR model. Samples sequenced in this study are represented in red. The green sequences correspond to Gabonese sequences recently described. The green framed sequences correspond to the potential recombinant (GenBank accession number of referenced strains, Genotypes and Countries of origin are indicated in the tree). Only Branching Posterior Probability (BPP) values ≥ 70% are illustrated.</p

Research paper thumbnail of 8th IAS Conference on HIV Pathogenesis, Treatment & Prevention 19-22 July 2015, Vancouver, Canada

Journal of the International AIDS Society, 2015

Research paper thumbnail of Evaluation and Prevalence of Hepatitis B among Blood Donors in January - June 2013 Gabon

Journal of Human Virology & Retrovirology, 2015

Introduction: Infection with the hepatitis B virus (HBV) according to WHO, is a worldwide public ... more Introduction: Infection with the hepatitis B virus (HBV) according to WHO, is a worldwide public health problem. Very few data available on the prevalence of HBs antigen in blood donors in the national context in Gabon. To better understand the epidemiological aspects necessary to develop a program to fight against viral hepatitis, including HBsAg in blood donors in Gabon.

Research paper thumbnail of HIV protease resistance mutations in patients receiving second-line antiretroviral therapy in Libreville, Gabon

BMC infectious diseases, Mar 14, 2024

Introduction In 2022, the WHO reported that 29.8 million people around the world were living with... more Introduction In 2022, the WHO reported that 29.8 million people around the world were living with HIV (PLHIV) and receiving antiretroviral treatment (ART), including 25 375 people in Gabon (54% of all those living with HIV in the country). The literature reports a frequency of therapeutic failure with first-line antiretrovirals (ARVs) of between 20% and 82%. Unfortunately, data relating to the failure of second-line ARVs are scarce in Gabon. This study aims to determine the profiles of HIV drug resistance mutations related to protease inhibitors in Gabon. Methodology Plasma from 84 PLHIV receiving ARVs was collected from 2019 to 2021, followed by RNA extraction, amplification, and sequencing of the protease gene. ARV resistance profiles were generated using the Stanford interpretation algorithm version 8.9-1 (https://hivdb.stanford.edu) and statistical analyses were performed using EpiInfo software version 7.2.1.0 (CDC, USA). Results Of 84 HIV plasma samples collected from 45 men and 39 women, 342 mutations were detected. Of these, 43.3% (148/342) were associated with nucleoside reverse transcriptase inhibitors (NRTIs), 30.4% (104/342) with nonnucleoside reverse transcriptase inhibitors (NNRTIs), and 26.3% (90/342) with protease inhibitors (PIs). Most NRTI mutations were associated with thymidine analogues (TAMs)

Research paper thumbnail of Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination

<p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and... more <p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination.</p

Research paper thumbnail of Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination

<p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and... more <p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination.</p

Research paper thumbnail of Hepatitis B infection among HIV infected individuals in Gabon: Occult hepatitis B enhances HBV DNA prevalence

PLOS ONE, 2018

In Gabon, a central African country, human immunodeficiency virus (HIV) and hepatitis B virus (HB... more In Gabon, a central African country, human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are endemic. In a recent study, conducted in a semi-urban area (Franceville, Gabon), HBV infection was found to be more prevalent among HIV infected individuals. This study aims to investigate the prevalence and genetic diversity of hepatitis B virus infection among HIV infected individuals, predominantly under antiretroviral therapy, living in fully urbanized area: Libreville, capital of Gabon. Serological and molecular tests were performed to detect HBV infection among patients living with HIV/AIDS (PLHA). We used Monolisa HBsAg ULTRA, Anti-HBc Plus and Anti-HBs Plus EIA kits for serological analyses. HBV DNA viral load (HBV DNA VL) was determined by real time PCR and molecular characterization of HBV strains was performed by sequencing and phylogenetic analysis of partial HBV surface and core genes. At all, 70.2% of patients were under antiretroviral therapy. The prevalence of HBsAg was 8.8% (43/487). Detectable HBV DNA was found in 69.7% (30/43) of HBsAg positive patients and in 17.5% (24/137) HBsAg negative patients. HBV DNA VL was significantly higher among patient with CD4 cell counts less than 200 cells/ mm 3 than those with CD4 cell counts greater than 500 cells/mm 3 (p = 0.008). We confirmed the presence of HBV sub-genotypes QS-A3 (40%), and A4 (20%) and HBV-E genotype (40%). The percentage of resistance to Lamivudine was high (40%) and varied according to the M204V/I motif. Occult hepatitis B infection (OBI) was found in patients with isolated HBcAb and among patients who had completed their HBsAg seroconversion. We detected HBV DNA for one patient without any HBV serological marker. This study provides a new landmark for the comprehension of HBV infection in PLHA in urban areas. OBI enhances HBV DNA prevalence and should be investigated in all HBsAg negative individuals.

Research paper thumbnail of Patients characteristics corresponding to the sequenced strains

<p>Patients characteristics corresponding to the sequenced strains.</p

Research paper thumbnail of HBV DNA detection and HBV DNA VL according to HBV serological profiles

<p>HBV DNA detection and HBV DNA VL according to HBV serological profiles.</p

Research paper thumbnail of Percentage of patients untreated versus treated, and distribution of antiviral HBV therapies

<p>Percentage of patients untreated versus treated, and distribution of antiviral HBV thera... more <p>Percentage of patients untreated versus treated, and distribution of antiviral HBV therapies.</p

Research paper thumbnail of Baseline characteristics and HBsAg prevalence in the studied population

<p>Baseline characteristics and HBsAg prevalence in the studied population.</p

Research paper thumbnail of Distribution of mutations in the Polymerase gene (A) and in S gene (B) using Mutation Reporter Tool (http://hvdr.bioinf.wits.ac.za/tools/)

<p>Letters preceding each locus on the X axis show the reference patterns and the letters i... more <p>Letters preceding each locus on the X axis show the reference patterns and the letters indexed in colors show the mutated patterns. Only detected mutations are represented.</p

Research paper thumbnail of Phylogenetic analysis of partial surface gene (Fig 3A) and core gene (Fig 3B) rooted on HBV woolly monkey strain (AY226578)

<p>This tree was inferred by the Bayesian method in the GTR model. Samples sequenced in thi... more <p>This tree was inferred by the Bayesian method in the GTR model. Samples sequenced in this study are represented in red. The green sequences correspond to Gabonese sequences recently described. The green framed sequences correspond to the potential recombinant (GenBank accession number of referenced strains, Genotypes and Countries of origin are indicated in the tree). Only Branching Posterior Probability (BPP) values ≥ 70% are illustrated.</p

Research paper thumbnail of 8th IAS Conference on HIV Pathogenesis, Treatment & Prevention 19-22 July 2015, Vancouver, Canada

Journal of the International AIDS Society, 2015

Research paper thumbnail of Evaluation and Prevalence of Hepatitis B among Blood Donors in January - June 2013 Gabon

Journal of Human Virology & Retrovirology, 2015

Introduction: Infection with the hepatitis B virus (HBV) according to WHO, is a worldwide public ... more Introduction: Infection with the hepatitis B virus (HBV) according to WHO, is a worldwide public health problem. Very few data available on the prevalence of HBs antigen in blood donors in the national context in Gabon. To better understand the epidemiological aspects necessary to develop a program to fight against viral hepatitis, including HBsAg in blood donors in Gabon.

Research paper thumbnail of HIV protease resistance mutations in patients receiving second-line antiretroviral therapy in Libreville, Gabon

BMC infectious diseases, Mar 14, 2024

Introduction In 2022, the WHO reported that 29.8 million people around the world were living with... more Introduction In 2022, the WHO reported that 29.8 million people around the world were living with HIV (PLHIV) and receiving antiretroviral treatment (ART), including 25 375 people in Gabon (54% of all those living with HIV in the country). The literature reports a frequency of therapeutic failure with first-line antiretrovirals (ARVs) of between 20% and 82%. Unfortunately, data relating to the failure of second-line ARVs are scarce in Gabon. This study aims to determine the profiles of HIV drug resistance mutations related to protease inhibitors in Gabon. Methodology Plasma from 84 PLHIV receiving ARVs was collected from 2019 to 2021, followed by RNA extraction, amplification, and sequencing of the protease gene. ARV resistance profiles were generated using the Stanford interpretation algorithm version 8.9-1 (https://hivdb.stanford.edu) and statistical analyses were performed using EpiInfo software version 7.2.1.0 (CDC, USA). Results Of 84 HIV plasma samples collected from 45 men and 39 women, 342 mutations were detected. Of these, 43.3% (148/342) were associated with nucleoside reverse transcriptase inhibitors (NRTIs), 30.4% (104/342) with nonnucleoside reverse transcriptase inhibitors (NNRTIs), and 26.3% (90/342) with protease inhibitors (PIs). Most NRTI mutations were associated with thymidine analogues (TAMs)

Research paper thumbnail of Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination

<p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and... more <p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination.</p

Research paper thumbnail of Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination

<p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and... more <p>Rate of detectable and undetectable HBV DNA, among the treated and untreated groups, and comparing different therapeutic combination.</p

Research paper thumbnail of Hepatitis B infection among HIV infected individuals in Gabon: Occult hepatitis B enhances HBV DNA prevalence

PLOS ONE, 2018

In Gabon, a central African country, human immunodeficiency virus (HIV) and hepatitis B virus (HB... more In Gabon, a central African country, human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are endemic. In a recent study, conducted in a semi-urban area (Franceville, Gabon), HBV infection was found to be more prevalent among HIV infected individuals. This study aims to investigate the prevalence and genetic diversity of hepatitis B virus infection among HIV infected individuals, predominantly under antiretroviral therapy, living in fully urbanized area: Libreville, capital of Gabon. Serological and molecular tests were performed to detect HBV infection among patients living with HIV/AIDS (PLHA). We used Monolisa HBsAg ULTRA, Anti-HBc Plus and Anti-HBs Plus EIA kits for serological analyses. HBV DNA viral load (HBV DNA VL) was determined by real time PCR and molecular characterization of HBV strains was performed by sequencing and phylogenetic analysis of partial HBV surface and core genes. At all, 70.2% of patients were under antiretroviral therapy. The prevalence of HBsAg was 8.8% (43/487). Detectable HBV DNA was found in 69.7% (30/43) of HBsAg positive patients and in 17.5% (24/137) HBsAg negative patients. HBV DNA VL was significantly higher among patient with CD4 cell counts less than 200 cells/ mm 3 than those with CD4 cell counts greater than 500 cells/mm 3 (p = 0.008). We confirmed the presence of HBV sub-genotypes QS-A3 (40%), and A4 (20%) and HBV-E genotype (40%). The percentage of resistance to Lamivudine was high (40%) and varied according to the M204V/I motif. Occult hepatitis B infection (OBI) was found in patients with isolated HBcAb and among patients who had completed their HBsAg seroconversion. We detected HBV DNA for one patient without any HBV serological marker. This study provides a new landmark for the comprehension of HBV infection in PLHA in urban areas. OBI enhances HBV DNA prevalence and should be investigated in all HBsAg negative individuals.