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Dive into the research topics where Barbara Gunsenheimer-Bartmeyer is active.

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Featured researches published by Barbara Gunsenheimer-Bartmeyer.


PLOS ONE | 2015

High Prevalence and High Incidence of Coinfection with Hepatitis B, Hepatitis C, and Syphilis and Low Rate of Effective Vaccination against Hepatitis B in HIV-Positive Men Who Have Sex with Men with Known Date of HIV Seroconversion in Germany

Klaus Jansen; Michael Thamm; Claus-Thomas Bock; Claudia Kücherer; Dieter Muenstermann; Hans-Jochen Hagedorn; Heiko Jessen; Stephan Dupke; Osamah Hamouda; Barbara Gunsenheimer-Bartmeyer; Karolin Meixenberger

Objectives Men who have sex with men (MSM) are at higher risk for coinfection with hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis than the general population. HIV infection and these coinfections accelerate disease progression reciprocally. This study evaluated the prevalence and incidence of these coinfections in HIV1-positive MSM in Germany. Materials and Methods As part of a nationwide, multicenter, prospective cohort study of HIV-infected MSM, plasma samples collected yearly were screened for HBsAg and antibodies to HBc, HBs, HCV, and syphilis. Samples with indications of active HBV or HCV infection were confirmed by polymerase chain reaction. Prevalence and incidence of each infection and incidence rates per study participant were calculated, and incidences over 4-year time intervals compared. Results This study screened 5,445 samples from 1,843 MSM. Median age at HIV seroconversion was 33 years. Prevalences of active, cleared, and occult HBV, and of active/cleared HCV were 1.7%, 27.1%, 0.2%, and 8.2%, respectively, and 47.5% had been effectively vaccinated against HBV. Prevalence of antibodies to Treponema pallidum and of triple or quadruple sexually transmitted infections (STIs) were 39.6% and 18.9%, respectively. Prevalence of STI, cleared HBV, HBV vaccination, and history of syphilis differed significantly among age groups. Incidences of HBV, HCV, and syphilis were 2.51, 1.54, and 4.06 per 100 person-years, respectively. Incidences of HCV and syphilis increased over time. HCV incidence was significantly higher in MSM coinfected with syphilis and living in Berlin, and syphilis incidence was significantly higher for MSM living in Berlin. Discussion Despite extensive HBV vaccination campaigns, fewer than 50% of screened MSM were effectively vaccinated, with a high proportion of HIV-positive MSM coinfected with HBV. High rates of STI coinfections in HIV-positive MSM and increasing incidences emphasize the need for better tailored campaigns for HBV vaccination and STI prevention.


Eurosurveillance | 2015

Late presentation for HIV care across Europe: Update from the collaboration of observational HIV epidemiological research europe (COHERE) study, 2010 to 2013

Osamah Hamouda; Barbara Gunsenheimer-Bartmeyer

Late presentation (LP) for HIV care across Europe remains a significant issue. We provide a cross-European update from 34 countries on the prevalence and risk factors of LP for 2010-2013. People aged ≥ 16 presenting for HIV care (earliest of HIV-diagnosis, first clinic visit or cohort enrollment) after 1 January 2010 with available CD4 count within six months of presentation were included. LP was defined as presentation with a CD4 count < 350/mm(3) or an AIDS defining event (at any CD4), in the six months following HIV diagnosis. Logistic regression investigated changes in LP over time. A total of 30,454 people were included. The median CD4 count at presentation was 368/mm(3) (interquartile range (IQR) 193-555/mm(3)), with no change over time (p = 0.70). In 2010, 4,775/10,766 (47.5%) were LP whereas in 2013, 1,642/3,375 (48.7%) were LP (p = 0.63). LP was most common in central Europe (4,791/9,625, 49.8%), followed by northern (5,704/11,692; 48.8%), southern (3,550/7,760; 45.8%) and eastern Europe (541/1,377; 38.3%; p < 0.0001). There was a significant increase in LP in male and female people who inject drugs (PWID) (adjusted odds ratio (aOR)/year later 1.16; 95% confidence interval (CI): 1.02-1.32), and a significant decline in LP in northern Europe (aOR/year later 0.89; 95% CI: 0.85-0.94). Further improvements in effective HIV testing strategies, with a focus on vulnerable groups, are required across the European continent.Late presentation (LP) for HIV care across Europe remains a significant issue. We provide a cross-European update from 34 countries on the prevalence and risk factors of LP for 2010-2013. People aged ≥ 16 presenting for HIV care (earliest of HIV-diagnosis, first clinic visit or cohort enrollment) after 1 January 2010 with available CD4 count within six months of presentation were included. LP was defined as presentation with a CD4 count < 350/mm(3) or an AIDS defining event (at any CD4), in the six months following HIV diagnosis. Logistic regression investigated changes in LP over time. A total of 30,454 people were included. The median CD4 count at presentation was 368/mm(3) (interquartile range (IQR) 193-555/mm(3)), with no change over time (p = 0.70). In 2010, 4,775/10,766 (47.5%) were LP whereas in 2013, 1,642/3,375 (48.7%) were LP (p = 0.63). LP was most common in central Europe (4,791/9,625, 49.8%), followed by northern (5,704/11,692; 48.8%), southern (3,550/7,760; 45.8%) and eastern Europe (541/1,377; 38.3%; p < 0.0001). There was a significant increase in LP in male and female people who inject drugs (PWID) (adjusted odds ratio (aOR)/year later 1.16; 95% confidence interval (CI): 1.02-1.32), and a significant decline in LP in northern Europe (aOR/year later 0.89; 95% CI: 0.85-0.94). Further improvements in effective HIV testing strategies, with a focus on vulnerable groups, are required across the European continent.


BMC Infectious Diseases | 2014

Tuberculosis among people living with HIV/AIDS in the German ClinSurv HIV Cohort: long-term incidence and risk factors

Basel Karo; Walter Haas; Christian Kollan; Barbara Gunsenheimer-Bartmeyer; Osamah Hamouda; Lena Fiebig

BackgroundTuberculosis (TB) still presents a leading cause of morbidity and mortality among people living with HIV/AIDS (PLWHA), including those on antiretroviral therapy. In this study, we aimed to determine the long-term incidence density rate (IDR) of TB and risk factors among PLWHA in relation to combination antiretroviral therapy (cART)-status.MethodsData of PLWHA enrolled from 2001 through 2011 in the German ClinSurv HIV Cohort were investigated using survival analysis and Cox regression.ResultsTB was diagnosed in 233/11,693 PLWHA either at enrollment (N = 62) or during follow-up (N = 171). The TB IDR during follow-up was 0.37 cases per 100 person-years (PY) overall [95% CI, 0.32-0.43], and was higher among patients who never started cART and among patients originating from Sub-Saharan Africa (1.23 and 1.20 per 100PY, respectively). In two multivariable analyses, both patients (I) who never started cART and (II) those on cART shared the same risk factors for TB, namely: originating from Sub-Saharan Africa compared to Germany (I, hazard ratio (HR); [95% CI]) 4.05; [1.87-8.78] and II, HR 5.15 [2.76-9.60], CD4+ cell count <200 cells/μl (I, HR 8.22 [4.36-15.51] and II, HR 1.90 [1.14-3.15]) and viral load >5 log10 copies/ml (I, HR 2.51 [1.33-4.75] and II, HR 1.77 [1.11-2.82]). Gender, age or HIV-transmission risk group were not independently associated with TB.ConclusionIn the German ClinSurv HIV cohort, patients originating from Sub-Saharan Africa, with low CD4+ cell count or high viral load at enrollment were at increased risk of TB even after cART initiation. As patients might be latently infected with Mycobacterium tuberculosis complex, early screening for latent TB infection and implementing isoniazid preventive therapy in line with available recommendations is crucial.


Sexually Transmitted Infections | 2010

Time trends of syphilis and HSV-2 co-infection among men who have sex with men in the German HIV-1 seroconverter cohort from 1996–2007

Nadine Spielmann; D Münstermann; Hans-Jochen Hagedorn; Matthias an der Heiden; Claudia Houareau; Barbara Gunsenheimer-Bartmeyer; Claudia Kücherer; Katrin Keeren; Osamah Hamouda; Ulrich Marcus

Objectives Numbers of newly diagnosed HIV infections among men who have sex with men (MSM) in Germany increased after the year 2000. We sought to explore trends in STI co-infections around the time of HIV seroconversion in patients from the German HIV-1 seroconverter cohort from 1996–2007. Methods MSM from the cohort were included for secondary analysis, if seroconversion occurred between 1996 and 2007 and if a blood sample taken within 2 y after HIV infection was available for further testing. Samples were tested for antibodies against Treponema pallidum and HSV-2. A classification system was developed to assign the chronology of syphilis and HIV-1 infection. Results Data of 1052 MSM were eligible for analysis. Overall seroprevalence of syphilis markers was 26%, increasing from 10% (1996–1999) to 35% (2005). Among HIV seroconverters with positive syphilis antibodies, 32% (n=88) were rated as having had coincident infections with HIV and syphilis. Coincident syphilis infection at HIV diagnosis increased substantially (p<0.001) from 2.3% in 2000 to 16.9% in 2003; and thereafter declined to 4.3% in 2007. Mean HSV-2 antibody prevalence was 40.5%, mean anti-HSV-2 IgM prevalence was 11.2%, with no significant change over time. Discussion We found a stable prevalence of HSV-2 infection and increasing prevalence of syphilis infection around the time of HIV acquisition among MSM in Germany. Time course and rate of co-infections suggest that a re-emerging syphilis co-epidemic among MSM after 2000 could have contributed to an increase of HIV incidence by enhancing HIV transmission probability.


Clinical Infectious Diseases | 2017

The Human Immunodeficiency Virus Continuum of Care in European Union Countries in 2013: Data and Challenges

Annabelle Gourlay; Teymur Noori; Anastasia Pharris; Maria Axelsson; Dominique Costagliola; Susan Cowan; Sara Croxford; Antonella d'Arminio Monforte; Julia del Amo; Valerie Delpech; Asunción Díaz; Enrico Girardi; Barbara Gunsenheimer-Bartmeyer; Victoria Hernando; Sophie Jose; Gisela Leierer; Georgios K. Nikolopoulos; Niels Obel; Eline Op de Coul; Dimitra Paraskeva; Peter Reiss; Caroline Sabin; André Sasse; Daniela Schmid; Anders Sönnerborg; Alexander Spina; Barbara Suligoi; Virginie Supervie; Giota Touloumi; Dominique Van Beckhoven

Summary Definitions for a 4-stage continuum of HIV care were standardized and applied to HIV surveillance and national cohort data in 11 European Union countries. These countries are nearing the UNAIDS 90-90-90 target, although reducing the proportion undiagnosed remains challenging.


PLOS ONE | 2012

HIV-Prevalence in Tuberculosis Patients in Germany, 2002–2009: An Estimation Based on HIV and Tuberculosis Surveillance Data

Lena Fiebig; Christian Kollan; Barbara Hauer; Barbara Gunsenheimer-Bartmeyer; Matthias an der Heiden; Osamah Hamouda; Walter Haas

Tuberculosis (TB) and HIV comorbidity is a major challenge in TB prevention and control but difficult to assess in Germany as in other countries, where data confidentiality precludes notifying the HIV status of TB patients. We aimed to estimate the HIV-prevalence in TB patients in Germany, 2002–2009, and to characterize the HIV/TB patients demographically. Data from the long-term observational open multicentre cohort ClinSurv HIV were used to identify incident TB in HIV-positive individuals. We assessed the cohort’s coverage for the nationwide HIV-positive population by contrasting ClinSurv HIV patients under antiretroviral therapy (ART) with national HIV patient numbers derived from ART prescriptions (data by Insight Health; available for 2006–2009). The HIV-prevalence in TB patients was calculated as the number of HIV/TB cases projected for Germany over all culture-positive TB notifications. From 2002 to 2009, 298 of 15,531 HIV-positive patients enrolled in the ClinSurv HIV cohort were diagnosed with TB. A 21% cohort coverage was determined. The annual estimates of the HIV-prevalence in TB patients were on average 4.5% and ranged from 3.5% (95%CI 2.3–5.1%) in 2007 to 6.6% (95%CI 5.0–8.5%) in 2005. The most recent estimate for 2009 was 4.0% (95%CI 2.6–5.9%). The 298 HIV/TB patients were characterized by a male-to-female ratio of 2.1, by a median age of 38 years at TB diagnosis, and by 59% of the patients having a foreign origin, mainly from Subsahara Africa. We provide, to our knowledge, the first estimate of the HIV-prevalence in TB patients for Germany by joint evaluation of anonymous HIV and TB surveillance data sources. The identified level of HIV in TB patients approximates available surveillance data from neighbouring countries and indicates a non-negligible HIV/TB burden in Germany. Our estimation approach is valuable for epidemiological monitoring of HIV/TB within the current legal frameworks.


The Lancet HIV | 2017

New HIV diagnoses among adults aged 50 years or older in 31 European countries, 2004–15: an analysis of surveillance data

Lara Tavoschi; Joana Gomes Dias; Anastasia Pharris; Daniela Schmid; André Sasse; Dominique Van Beckhoven; Tonka Varleva; Tatjana Nemeth Blazic; Linos Hadjihannas; Maria Koliou; Marek Maly; Susan Cowan; Kristi Rüütel; Kirsi Liitsola; Mika Salminen; Françoise Cazein; Josiane Pillonel; Florence Lot; Barbara Gunsenheimer-Bartmeyer; Stavros Patrinos; Dimitra Paraskeva; Maria Dudas; Haraldur Briem; Gudrun Sigmundsdottir; Derval Igoe; Kate O'Donnell; Darina O'Flanagan; Barbara Suligoi; Šarlote Konova; Sabine Erne

BACKGROUND The HIV burden is increasing in older adults in the European Union (EU) and European Economic Area (EEA). We investigated factors associated with HIV diagnosis in older adults in the 31 EU/EEA countries during a 12 year period. METHODS In this analysis of surveillance data, we compared data from older people (aged ≥50 years) with those from younger people (aged 15-49 years). We extracted new HIV diagnoses reported to the European Surveillance System between Jan 1, 2004, and Dec 31, 2015, and stratified them by age, sex, migration status, transmission route, and CD4 cell count. We defined late diagnosis as CD4 count of less than 350 cells per μL at diagnosis and diagnosis with advanced HIV disease as less than 200 cells per μL. We compared the two age groups with the χ2 test for difference, and used linear regression analysis to assess temporal trends. FINDINGS During the study period 54 102 new HIV diagnoses were reported in older adults. The average notification rate of new diagnoses was 2·6 per 100 000 population across the whole 12 year period, which significantly increased over time (annual average change [AAC] 2·1%, 95% CI 1·1-3·1; p=0·0009). Notification rates for new HIV diagnoses in older adults increased significantly in 16 countries in 2004-15, clustering in central and eastern EU/EEA countries. In 2015, compared with younger adults, older individuals were more likely to originate from the reporting country, to have acquired HIV via heterosexual contact, and to present late (p<0·0001 for all comparisons). HIV diagnoses increased significantly over time among older men (AAC 2·2%, 95% CI 1·2-3·3; p=0·0006), women (1·3%, 0·2-2·4; p=0·025), men who have sex with men (5·8%, 4·3-7·5; p<0·0001), and injecting drug users (7·4%, 4·8-10·2; p<0·0001). INTERPRETATION Our findings suggest that there is a compelling need to deliver more targeted testing interventions for older adults and the general adult population, such as by increasing awareness among health-care workers and expanding opportunities for provider-initiated and indicator-condition-guided testing programmes. FUNDING European Centre for Disease Prevention and Control.


PLOS Biology | 2017

Viral genetic variation accounts for a third of variability in HIV-1 set-point viral load in Europe.

François Blanquart; Chris Wymant; Marion Cornelissen; Astrid Gall; Margreet Bakker; Daniela Bezemer; Matthew Hall; Mariska Hillebregt; Swee Hoe Ong; Jan Albert; Norbert Bannert; Jacques Fellay; Katrien Fransen; Annabelle Gourlay; M. Kate Grabowski; Barbara Gunsenheimer-Bartmeyer; Huldrych F. Guenthard; Pia Kivelä; Roger D. Kouyos; Oliver Laeyendecker; Kirsi Liitsola; Laurence Meyer; Kholoud Porter; Matti Ristola; Ard van Sighem; Guido Vanham; Ben Berkhout; Paul Kellam; Peter Reiss; Christophe Fraser

HIV-1 set-point viral load—the approximately stable value of viraemia in the first years of chronic infection—is a strong predictor of clinical outcome and is highly variable across infected individuals. To better understand HIV-1 pathogenesis and the evolution of the viral population, we must quantify the heritability of set-point viral load, which is the fraction of variation in this phenotype attributable to viral genetic variation. However, current estimates of heritability vary widely, from 6% to 59%. Here we used a dataset of 2,028 seroconverters infected between 1985 and 2013 from 5 European countries (Belgium, Switzerland, France, the Netherlands and the United Kingdom) and estimated the heritability of set-point viral load at 31% (CI 15%–43%). Specifically, heritability was measured using models of character evolution describing how viral load evolves on the phylogeny of whole-genome viral sequences. In contrast to previous studies, (i) we measured viral loads using standardized assays on a sample collected in a strict time window of 6 to 24 months after infection, from which the viral genome was also sequenced; (ii) we compared 2 models of character evolution, the classical “Brownian motion” model and another model (“Ornstein–Uhlenbeck”) that includes stabilising selection on viral load; (iii) we controlled for covariates, including age and sex, which may inflate estimates of heritability; and (iv) we developed a goodness of fit test based on the correlation of viral loads in cherries of the phylogenetic tree, showing that both models of character evolution fit the data well. An overall heritability of 31% (CI 15%–43%) is consistent with other studies based on regression of viral load in donor–recipient pairs. Thus, about a third of variation in HIV-1 virulence is attributable to viral genetic variation.


Clinical Infectious Diseases | 2018

Global Trends in CD4 Cell Count at the Start of Antiretroviral Therapy: Collaborative Study of Treatment Programs

Nanina Anderegg; Klea Panayidou; Yao Abo; Belén Alejos; Keri N. Althoff; Kathryn Anastos; Andrea Antinori; Eric Balestre; Renaud Becquet; Antonella Castagna; Barbara Castelnuovo; Geneviève Chêne; Lara Coelho; Intira Jeannie Collins; Dominique Costagliola; Crabtree-Ramirez B; François Dabis; Antonella d'Arminio Monforte; Mary-Ann Davies; Stéphane De Wit; Valerie Delpech; Nicole L. De La Mata; Stephany N. Duda; Aimee M. Freeman; Stephen J. Gange; Katharina Grabmeier-Pfistershammer; Barbara Gunsenheimer-Bartmeyer; Awachana Jiamsakul; Mari M. Kitahata; Matthew Law

We modeled global time trends in median CD4 cell counts at combination antiretroviral therapy initiation in human immunodeficiency virus–infected adults. These counts have increased in all country income groups since 2002 but generally remained below 350/μL in 2015.


bioRxiv | 2016

Easy and Accurate Reconstruction of Whole HIV Genomes from Short-Read Sequence Data

Chris Wymant; François Blanquart; Astrid Gall; Margreet Bakker; Daniela Bezemer; Nicholas J. Croucher; Tanya Golubchik; Matthew Hall; Mariska Hillebregt; Swee Hoe Ong; Jan Albert; Norbert Bannert; Jacques Fellay; Katrien Fransen; Annabelle Gourlay; M. Kate Grabowski; Barbara Gunsenheimer-Bartmeyer; Huldrych F. Günthard; Pia Kivelä; Roger D. Kouyos; Oliver Laeyendecker; Kirsi Liitsola; Laurence Meyer; Kholoud Porter; Matti Ristola; Ard van Sighem; Guido Vanham; Ben Berkhout; Marion Cornelissen; Paul Kellam

Next-generation sequencing has yet to be widely adopted for HIV. The difficulty of accurately reconstructing the consensus sequence of a quasispecies from reads (short fragments of DNA) in the presence of rapid between- and within-host evolution may have presented a barrier. In particular, mapping (aligning) reads to a reference sequence leads to biased loss of information; this bias can distort epidemiological and evolutionary conclusions. De novo assembly avoids this bias by effectively aligning the reads to themselves, producing a set of sequences called contigs. However contigs provide only a partial summary of the reads, misassembly may result in their having an incorrect structure, and no information is available at parts of the genome where contigs could not be assembled. To address these problems we developed the tool shiver to preprocess reads for quality and contamination, then map them to a reference tailored to the sample using corrected contigs supplemented with existing reference sequences. Run with two commands per sample, it can easily be used for large heterogeneous data sets. We use shiver to reconstruct the consensus sequence and minority variant information from paired-end short-read data produced with the Illumina platform, for 65 existing publicly available samples and 50 new samples. We show the systematic superiority of mapping to shiver’s constructed reference over mapping the same reads to the standard reference HXB2: an average of 29 bases per sample are called differently, of which 98.5% are supported by higher coverage. We also provide a practical guide to working with imperfect contigs.

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Kholoud Porter

University College London

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Giota Touloumi

National and Kapodistrian University of Athens

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Susan Cowan

Statens Serum Institut

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Kirsi Liitsola

National Institute for Health and Welfare

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