Ulrich Marcus
Datos Biográficos
| ID | 5221643 |
|---|---|
| NOMBRE | Ulrich Marcus |
| NOMBRES | Ulrich |
| APELLIDO | Marcus |
| FIRMA | MARCUS U |
| AFILIACIONES | Robert Koch Institute |
| ORCID | 0000-0002-3143-2717 |
| VERIFICADO | Sí |
| TOTAL DE OBRAS | 32 |
| TOTAL DE CITAS | 23 |
| TOTAL COMO AUTOR | 32 |
| TOTAL COMO EDITOR | 0 |
| PRIMER AÑO DE PUBLICACIÓN | 2009 |
| AÑO MÁS RECIENTE DE PUBLICACIÓN | 2026 |
| ÍNDICE H | 3 |
Analysis of potential barriers for PrEP non-users among PrEP-eligible MSM in Germany
The potential of routine surveillance data for identifying the needs of people living with HIV among migrants
Since the start of Russia’s war against Ukraine, more than one million people from Ukraine – a country with high Human Immunodeficiency Virus (HIV)-prevalence – have fled to Germany. We aimed to estimate the number of people living with HIV (PLHIV) with a link to Ukraine reported to the German HIV notification system, analyse their characteristics and estimate the proportion of prior known infections to better understand the care needs of this po…
European Men-Who-Have-Sex-With-Men and Trans People Internet Survey (Emis-2024)
Men-who-have-sex-with-men (MSM), as well as transgender and non-binary individuals, continue to face a disproportionate burden of stigma, mental health challenges, HIV, and other sexually transmitted infections. To address their needs, public health planners require reliable and comparable data. Monitoring behaviours in these populations also supports the evaluation of health policies. The European-MSM-Internet-Survey (EMIS-2024) builds on our in…
Dynamics of HIV PrEP use and coverage during and after Covid-19 in Germany
Our approach presents a comprehensive solution to monitor and forecast PrEP implementation from anonymous data and highlighted that the COVID-19 pandemic significantly decelerated PrEP uptake in Germany. Moreover, slow PrEP uptake in rural areas indicate that structural barriers in PrEP care, education or information exist that may hamper the goal of ending the AIDS epidemic by 2030
Association of internalised homonegativity with partner notification after diagnosis of syphilis or gonorrhoea among men having sex with men in 49 countries across four continents
We could demonstrate that IH was associated with PN among MSM across all countries included in our analysis. Reducing cultural homophobia and ensuring inclusive policies may contribute to STI prevention and control
Comparison of the burden of self-reported bacterial sexually transmitted infections among men having sex with men across 68 countries on four continents
Possible reasons for differences in self-reported STI diagnosis prevalence likely include different background prevalence for syphilis and syndromic management without proper diagnosis, and different diagnostic approaches for gonorrhea and chlamydia
HIV pre-exposure prophylaxis and diagnoses of sexually transmitted infections – observational data from German checkpoints, 01/2019–08/2021
Checkpoint visits reporting current PrEP use or intention to start PrEP correlated with eligibility criteria for PrEP, i.e. high partner numbers, inconsistent condom use during anal intercourse, and use of chemsex drugs. Use of HIV-specific prevention methods such as HIV serosorting, PrEP sorting, and viral load sorting was reported more frequently. (Daily) PrEP use was an independent risk factor for a chlamydia diagnosis only
The Role of Community Health Workers Within the Continuum of Services for HIV, Viral Hepatitis, and Other STIs Amongst Men Who Have Sex with Men in Europe
Process evaluation of a bio-behavioural HIV research combined with prevention among GBMSM in 13 European countries
Comparative European data using Second Generation Surveillance System (SGSS) are scarce among gay, bisexual and other men who have sex with men. This study evaluated the implementation of Sialon II, a bio-behavioural HIV research combined with targeted HIV prevention in 13 European cities conducted in collaboration with community partners. A mixed-methods process evaluation assessed the project's coverage, outputs, quality, challenges and opportu…
Barriers to using HIV pre-exposure prophylaxis (PrEP) and sexual behaviour after stopping PrEP
To maximise persistence with PrEP we need to develop strategies for younger PrEP users, reduce logistic barriers to access PrEP, and to develop effective communication on side-effect management. Moreover, prevention strategies for people stopping PrEP are required, since some remain at high risk for HIV
European Men-Who-Have-Sex-With-Men Internet Survey (Emis-2017)
Men-who-have-sex-with-men (MSM) carry a disproportionate burden of sexually transmitted infections across Europe. Health planners require sexual health needs assessment data to respond appropriately. In addition, surveillance of risk and precaution behaviours in this population enables evaluative judgements of policy responses. The European MSM Internet Survey (EMIS-2017) aimed to repeat the pan-European online survey on male homosexual behaviour…
Prevalence of drug use during sex amongst MSM in Europe
Risk behaviours and viral infections among drug injecting migrants from the former Soviet Union in Germany
The Geography of Sexual Orientation
Bio-behavioural HIV and STI surveillance among men who have sex with men in Europe
Through the implementation of combined and targeted prevention complemented by meaningful surveillance among MSM, Sialon II represents a unique opportunity to pilot a bio-behavioural survey in community settings in line with the SGSS approach in a large number of EU countries. Data generated through this survey will not only provide a valuable snapshot of the HIV epidemic in MSM but will also offer an important trend analysis of the epidemiology …
HIV risk perception and testing behaviours among men having sex with men (MSM) reporting potential transmission risks in the previous 12 months from a large online sample of MSM living in Germany
Perceived partner knowledge and reasons reflecting perceived gay- and HIV-related stigma predicted testing decisions rather than risk perception. Access barriers for testing should be further lowered, e.g. by making affordable HT available, addressing structural barriers (stigma), and emphasizing beneficial aspects of serostatus awareness
High variability of HIV and HCV seroprevalence and risk behaviours among people who inject drugs
In the recruited sample of mostly current injectors with a long duration of injecting drug use, seroprevalence for HIV and HCV varied greatly between the city samples. HCV was endemic among participants in all city samples. Our results demonstrate the necessity of intensified prevention strategies for blood-borne infections among PWID in Germany
Illicit drug use among gay and bisexual men in 44 cities
Hidden from health
OBJECTIVE: Substantial country-level variation exists in prejudiced attitudes towards male homosexuality and in the extent to which countries promote the unequal treatment of MSM through discriminatory laws. The impact and underlying mechanisms of country-level stigma on odds of diagnosed HIV, sexual opportunities, and experience of HIV-prevention services, needs and behaviours have rarely been examined, however. DESIGN: Data come from the Europe…
Factors associated with unprotected anal sex with multiple non-steady partners in the past 12 months
Effective antiretroviral treatment drastically reduces HIV transmission for men diagnosed with HIV, irrespective of partner numbers. Apart from reducing partner numbers or increasing condom use no other recommendations are currently in place to reduce the risk of HIV acquisition and onward transmission for HIV-negative men practicing UAI with multiple partners. A range of factors were identified as associated with UAI with four or more partners w…
Determinants of HIV, viral hepatitis and STI prevention needs among African migrants in Germany; a cross-sectional survey on knowledge, attitudes, behaviors and practices
Study participants demonstrated good knowledge on HIV-transmission but knowledge gaps regarding HIV/STI-testing services, HEP and STI. This calls for targeted interventions providing more information about these topics in African communities in Hamburg and possibly also elsewhere
Recency and frequency of HIV testing among men who have sex with men in Germany and socio-demographic factors associated with testing behaviour
MSM who were younger, who did not live in large cities, and who were not out about their sexual orientation tested less frequently for HIV. Apart from strengthening protection from sexual orientation-related discrimination and empowering MSM who conceal their orientation, more opportunities to test anonymously and without revealing one's sexual orientation should be provided
Factors associated with sexual risk behaviors with non-steady partners and lack of recent HIV testing among German men who have sex with men in steady relationships
Based on our results, we reflect on HIV prevention measures that should be improved in order to better target behaviors that may lead to HIV transmission between MSM in steady relationships. In particular, we highlight the need for multifaceted interventions focusing not only on members of the at-risk community themselves, but on communities as a whole
Conversation about Serostatus decreases risk of acquiring HIV
There were no significant differences regarding knowledge about HIV-transmission risks among cases and controls. Differences in risk behaviour were observed regarding unprotected sex with partners of unknown HIV-serostatus and duration of primary partnership at the time of diagnosis, suggesting some HIV-transmissions occurring in newly formed partnerships. The practice of discussing serostatus with prospective sex partners before engaging in sex …
A multicentre sero-behavioural survey for hepatitis B and C, HIV and HTLV among people who inject drugs in Germany using respondent driven sampling
We chose respondent driven sampling for recruitment of participants to improve representativeness of results. Persons, who are not reached by the facility where the study is conducted, are aimed to be included by recruitment through their personal social network of injecting drug users. To reduce differential biases in the questions on knowledge of transmission and prevention of infections, we present true statements on hepatitis B, C and HIV, th…
The Geography of Sexual Orientation
The European Men-Who-Have-Sex-With-Men Internet Survey (Emis)
Community-based opportunistic self-completion surveying for sexual health programming is common among men-who-have-sex-with-men (MSM) in Europe, being used to generate evidence of unmet prevention need, for behavioural surveillance and as a platform for advocating HIV precautions. However, comparing survey findings across Europe is difficult because of varying measures and recruitment designs, and surveying has not occurred in all countries. EMIS…
European Men-Who-Have-Sex-With-Men Internet Survey (Emis-2017)
Men-who-have-sex-with-men (MSM) carry a disproportionate burden of sexually transmitted infections across Europe. Health planners require sexual health needs assessment data to respond appropriately. In addition, surveillance of risk and precaution behaviours in this population enables evaluative judgements of policy responses. The European MSM Internet Survey (EMIS-2017) aimed to repeat the pan-European online survey on male homosexual behaviour…
Reemergence of the HIV Epidemic Among Men Who Have Sex With Men in North America, Western Europe, and Australia, 1996–2005
Estimating the regional distribution of men who have sex with men (MSM) based on Internet surveys
Considering the difficulties to obtain representative data by other sampling methods for "hidden" populations like MSM, internet-based surveys may provide an easy and low cost tool to estimate the regional population distribution -- at least in Western post-industrialized countries. Some uncertainties remain about the exact place of residence of MSM in larger cities or catchment areas of these cities. Slightly different results from different dat…
The denominator problem
Considering the difficulties to obtain regionally representative data by other sampling methods for MSM, in Western post-industrialized countries internet-based surveys may provide an easy and low cost tool to estimate regional population distributions. With national surveillance data, which categorize transmission groups, regional population-specific incidence rates for reportable sexually transmitted infections can be estimated. HIV prevalence …
Prevalence of HIV among MSM in Europe
Comparison of diagnosed HIV prevalence as measured in EMIS with pre-existing estimates based on biological measurements using varied sampling frames (e.g. Respondent Driven Sampling, Time and Location Sampling) demonstrates a high correlation and suggests similar selection biases from both types of studies. For comparison with modelled estimates the self-selection bias of the Internet survey with increased participation of men diagnosed with HIV …
Age biases in a large HIV and sexual behaviour-related internet survey among MSM
Internet samples are biased towards a lower median age because younger men are over-represented on MSM dating websites and therefore may be more likely to be recruited into surveys. Men diagnosed with HIV were over-represented in the internet survey, and increasingly so in the older age groups. A similar effect was observed in the age groups younger than 25 years. Self-reported peak prevalence and peak HIV diagnoses rates are often shifted to hig…
Estimating the size of the MSM populations for 38 European countries by calculating the survey-surveillance discrepancies (SSD) between self-reported new HIV diagnoses from the European MSM internet s…
Npop and HIVpop were unreliably low for several countries. We discuss and identify possible measurement errors for countries with calculated MSM population sizes above 3% and below 1% of the adult male population. In most cases the number of new HIV diagnoses in MSM in the surveillance system appears too low. In some cases, measurement errors may be due to small EMIS sample sizes. It must be assumed that the SSD is modified by country-specific fa…
The European Men-Who-Have-Sex-With-Men Internet Survey (Emis)
Community-based opportunistic self-completion surveying for sexual health programming is common among men-who-have-sex-with-men (MSM) in Europe, being used to generate evidence of unmet prevention need, for behavioural surveillance and as a platform for advocating HIV precautions. However, comparing survey findings across Europe is difficult because of varying measures and recruitment designs, and surveying has not occurred in all countries. EMIS…
Conversation about Serostatus decreases risk of acquiring HIV
There were no significant differences regarding knowledge about HIV-transmission risks among cases and controls. Differences in risk behaviour were observed regarding unprotected sex with partners of unknown HIV-serostatus and duration of primary partnership at the time of diagnosis, suggesting some HIV-transmissions occurring in newly formed partnerships. The practice of discussing serostatus with prospective sex partners before engaging in sex …
A multicentre sero-behavioural survey for hepatitis B and C, HIV and HTLV among people who inject drugs in Germany using respondent driven sampling
We chose respondent driven sampling for recruitment of participants to improve representativeness of results. Persons, who are not reached by the facility where the study is conducted, are aimed to be included by recruitment through their personal social network of injecting drug users. To reduce differential biases in the questions on knowledge of transmission and prevention of infections, we present true statements on hepatitis B, C and HIV, th…
Hidden from health
OBJECTIVE: Substantial country-level variation exists in prejudiced attitudes towards male homosexuality and in the extent to which countries promote the unequal treatment of MSM through discriminatory laws. The impact and underlying mechanisms of country-level stigma on odds of diagnosed HIV, sexual opportunities, and experience of HIV-prevention services, needs and behaviours have rarely been examined, however. DESIGN: Data come from the Europe…
Factors associated with unprotected anal sex with multiple non-steady partners in the past 12 months
Effective antiretroviral treatment drastically reduces HIV transmission for men diagnosed with HIV, irrespective of partner numbers. Apart from reducing partner numbers or increasing condom use no other recommendations are currently in place to reduce the risk of HIV acquisition and onward transmission for HIV-negative men practicing UAI with multiple partners. A range of factors were identified as associated with UAI with four or more partners w…
Determinants of HIV, viral hepatitis and STI prevention needs among African migrants in Germany; a cross-sectional survey on knowledge, attitudes, behaviors and practices
Study participants demonstrated good knowledge on HIV-transmission but knowledge gaps regarding HIV/STI-testing services, HEP and STI. This calls for targeted interventions providing more information about these topics in African communities in Hamburg and possibly also elsewhere
Recency and frequency of HIV testing among men who have sex with men in Germany and socio-demographic factors associated with testing behaviour
MSM who were younger, who did not live in large cities, and who were not out about their sexual orientation tested less frequently for HIV. Apart from strengthening protection from sexual orientation-related discrimination and empowering MSM who conceal their orientation, more opportunities to test anonymously and without revealing one's sexual orientation should be provided
Factors associated with sexual risk behaviors with non-steady partners and lack of recent HIV testing among German men who have sex with men in steady relationships
Based on our results, we reflect on HIV prevention measures that should be improved in order to better target behaviors that may lead to HIV transmission between MSM in steady relationships. In particular, we highlight the need for multifaceted interventions focusing not only on members of the at-risk community themselves, but on communities as a whole
Bio-behavioural HIV and STI surveillance among men who have sex with men in Europe
Through the implementation of combined and targeted prevention complemented by meaningful surveillance among MSM, Sialon II represents a unique opportunity to pilot a bio-behavioural survey in community settings in line with the SGSS approach in a large number of EU countries. Data generated through this survey will not only provide a valuable snapshot of the HIV epidemic in MSM but will also offer an important trend analysis of the epidemiology …
HIV risk perception and testing behaviours among men having sex with men (MSM) reporting potential transmission risks in the previous 12 months from a large online sample of MSM living in Germany
Perceived partner knowledge and reasons reflecting perceived gay- and HIV-related stigma predicted testing decisions rather than risk perception. Access barriers for testing should be further lowered, e.g. by making affordable HT available, addressing structural barriers (stigma), and emphasizing beneficial aspects of serostatus awareness
High variability of HIV and HCV seroprevalence and risk behaviours among people who inject drugs
In the recruited sample of mostly current injectors with a long duration of injecting drug use, seroprevalence for HIV and HCV varied greatly between the city samples. HCV was endemic among participants in all city samples. Our results demonstrate the necessity of intensified prevention strategies for blood-borne infections among PWID in Germany
Illicit drug use among gay and bisexual men in 44 cities
The Geography of Sexual Orientation
Prevalence of drug use during sex amongst MSM in Europe
Risk behaviours and viral infections among drug injecting migrants from the former Soviet Union in Germany
European Men-Who-Have-Sex-With-Men Internet Survey (Emis-2017)
Men-who-have-sex-with-men (MSM) carry a disproportionate burden of sexually transmitted infections across Europe. Health planners require sexual health needs assessment data to respond appropriately. In addition, surveillance of risk and precaution behaviours in this population enables evaluative judgements of policy responses. The European MSM Internet Survey (EMIS-2017) aimed to repeat the pan-European online survey on male homosexual behaviour…
The Role of Community Health Workers Within the Continuum of Services for HIV, Viral Hepatitis, and Other STIs Amongst Men Who Have Sex with Men in Europe
Process evaluation of a bio-behavioural HIV research combined with prevention among GBMSM in 13 European countries
Comparative European data using Second Generation Surveillance System (SGSS) are scarce among gay, bisexual and other men who have sex with men. This study evaluated the implementation of Sialon II, a bio-behavioural HIV research combined with targeted HIV prevention in 13 European cities conducted in collaboration with community partners. A mixed-methods process evaluation assessed the project's coverage, outputs, quality, challenges and opportu…
Barriers to using HIV pre-exposure prophylaxis (PrEP) and sexual behaviour after stopping PrEP
To maximise persistence with PrEP we need to develop strategies for younger PrEP users, reduce logistic barriers to access PrEP, and to develop effective communication on side-effect management. Moreover, prevention strategies for people stopping PrEP are required, since some remain at high risk for HIV
HIV/AIDS Research and Interventions (30 obras) · Medicine (29 obras) · Men who have sex with men (25 obras) · HIV, Drug Use, Sexual Risk (24 obras) · Family medicine (23 obras) · Demography (22 obras) · Biostatistics (21 obras) · Environmental health (21 obras) · Human immunodeficiency virus (HIV (21 obras) · Public health (21 obras)