André Jeannin
University of Lausanne
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AIDS | 2001
Florence Moreau-Gruet; André Jeannin; Françoise Dubois-Arber; Brenda Spencer
ObjectivesTo study the ways of managing HIV risk within male homosexual steady relationships (gay couples), including factors associated with consistent condom use during anal sex with the steady partner. MethodAn anonymous and standardized questionnaire completed by a convenience sample of homosexuals in Switzerland in 1997 (n = 1097). Information on the couple was provided by the 74% (n = 786) of male respondents who reported having a steady partner in the past 12 months. Data were analysed by contingency tables and logistic regression. ResultsDifferent ways of managing HIV risk were reported: negotiated safety (both HIV negative, condoms abandoned) was chosen by one quarter of the couples, but the most frequent solution was reliance on condoms for anal sex, chosen by more than four in 10. Altogether 84% of couples exhibited safe management of HIV risk within their partnership. The 16% of couples showing inadequate management of HIV risk within the couple mostly relied on questionable assumptions about past or present risks. A total of 74% of couples had spoken about managing HIV risk with possible casual partners. Reported behaviour with the steady partner and with casual partners was highly consistent with claimed strategies chosen to manage HIV risk. Consistent condom use with the steady partner was mostly associated with variables characterizing the relationship: initial 2 years of the relationship, discordant or unknown serological HIV status, non-exclusivity. ConclusionGay couples manage HIV risk in a variety of ways. Most strategies provide adequate protection with casual partners, but leave gaps in protection between the steady partners themselves.
PLOS ONE | 2012
Ard van Sighem; Beatriz Vidondo; Tracy R. Glass; Heiner C. Bucher; Pietro Vernazza; Martin Gebhardt; Frank de Wolf; Steven Derendinger; André Jeannin; Daniela Bezemer; Christophe Fraser; Nicola Low
Background New HIV infections in men who have sex with men (MSM) have increased in Switzerland since 2000 despite combination antiretroviral therapy (cART). The objectives of this mathematical modelling study were: to describe the dynamics of the HIV epidemic in MSM in Switzerland using national data; to explore the effects of hypothetical prevention scenarios; and to conduct a multivariate sensitivity analysis. Methodology/Principal Findings The model describes HIV transmission, progression and the effects of cART using differential equations. The model was fitted to Swiss HIV and AIDS surveillance data and twelve unknown parameters were estimated. Predicted numbers of diagnosed HIV infections and AIDS cases fitted the observed data well. By the end of 2010, an estimated 13.5% (95% CI 12.5, 14.6%) of all HIV-infected MSM were undiagnosed and accounted for 81.8% (95% CI 81.1, 82.4%) of new HIV infections. The transmission rate was at its lowest from 1995–1999, with a nadir of 46 incident HIV infections in 1999, but increased from 2000. The estimated number of new infections continued to increase to more than 250 in 2010, although the reproduction number was still below the epidemic threshold. Prevention scenarios included temporary reductions in risk behaviour, annual test and treat, and reduction in risk behaviour to levels observed earlier in the epidemic. These led to predicted reductions in new infections from 2 to 26% by 2020. Parameters related to disease progression and relative infectiousness at different HIV stages had the greatest influence on estimates of the net transmission rate. Conclusions/Significance The model outputs suggest that the increase in HIV transmission amongst MSM in Switzerland is the result of continuing risky sexual behaviour, particularly by those unaware of their infection status. Long term reductions in the incidence of HIV infection in MSM in Switzerland will require increased and sustained uptake of effective interventions.
European Journal of Epidemiology | 1998
André Jeannin; Elke Konings; Franqoise Dubois-Arber; Charles Landert; Guy van Melle
Objectives: To examine the validity and reliability of indicators of sexual behaviour and condom use in annual telephone surveys (n=2800) of the general population aged 17 to 45 for the evaluation of AIDS prevention in Switzerland. Methods: A test-retest study with additional focused interviews was conducted on a subsample (n=138) of the respondents aged 17 to 22 years. Results: The subsample included more French speaking respondents (OR: 1.7, CI: 1.1–2.5) and more people in a stable relationship (OR: 2.2, CI: 1.5–3–3) than the initial sample but did not differ in any other way, although no data is available on their attitudes towards sex. The reliability of the indicators considered was high: number of lifetime, casual sex partners in the last 6 months and condom use with them, acquisition of a new steady partner during the year and condom use with this partner, condom use at last intercourse. However, the focused interviews raised questions about the validity of some of these indicators, presumably due to imprecise wording of the questionnaire items. Among sexually active respondents, 12.5% (95% CI: 4.7–25.5) of the men included non-penetrative sex in the definition of ‘sexual intercourse’, but only 1.9% (95% CI: 0.1–10.3) of the women. The propensity for men of counting acts or partners with whom no penetration had taken place in the total reported sex acts or partners was not significantly associated with any socio-demographic variables. In addition, among the 15 respondents who had reported consistent condom use with casual sex partners at interview, 40% (95% CI: 16.3–67.7) admitted at reinterview that sometimes they also had unprotected sex. Conclusions: The reliability of reports on sexual behaviour and condom use in this Swiss evaluation survey is good. The indicators derived from the annual surveys are robust measures and the monitoring of trends seems to be based on reliable measurement. However, more research is required on the validity of the data.
Journal of Adolescent Health | 2008
Alexander T. Vazsonyi; Pan Chen; Maureen Young; Dusty D. Jenkins; Sara Browder; Emily Kahumoku; Karaman Pagava; Helen Phagava; André Jeannin; Pierre-André Michaud
PURPOSE The current study tested the applicability of Jessors problem behavior theory (PBT) in national probability samples from Georgia and Switzerland. Comparisons focused on (1) the applicability of the problem behavior syndrome (PBS) in both developmental contexts, and (2) on the applicability of employing a set of theory-driven risk and protective factors in the prediction of problem behaviors. METHODS School-based questionnaire data were collected from n = 18,239 adolescents in Georgia (n = 9499) and Switzerland (n = 8740) following the same protocol. Participants rated five measures of problem behaviors (alcohol and drug use, problems because of alcohol and drug use, and deviance), three risk factors (future uncertainty, depression, and stress), and three protective factors (family, peer, and school attachment). Final study samples included n = 9043 Georgian youth (mean age = 15.57; 58.8% females) and n = 8348 Swiss youth (mean age = 17.95; 48.5% females). Data analyses were completed using structural equation modeling, path analyses, and post hoc z-tests for comparisons of regression coefficients. RESULTS Findings indicated that the PBS replicated in both samples, and that theory-driven risk and protective factors accounted for 13% and 10% in Georgian and Swiss samples, respectively in the PBS, net the effects by demographic variables. Follow-up z-tests provided evidence of some differences in the magnitude, but not direction, in five of six individual paths by country. CONCLUSION PBT and the PBS find empirical support in these Eurasian and Western European samples; thus, Jessors theory holds value and promise in understanding the etiology of adolescent problem behaviors outside of the United States.
Journal of Medical Screening | 2001
Giovanna Meystre-Agustoni; Fred Paccaud; André Jeannin; Françoise Dubois-Arber
OBJECTIVES:To follow up anxiety in a cohort of women screened for breast cancer. METHODS:Within the framework of a pilot screening programme for breast cancer in the Canton of Vaud (Switzerland), a cohort of 924 participants aged 50–70 years were invited to answer questions on anxiety related to mammography screening. Anxiety was measured using a specific tool, the psychological consequences questionnaire (PCQ), and a new single item, direct question, breast cancer anxiety indicator (BCA). Participants were asked to fill in the questionnaire at four different phases: at screening, before the result, and 2 and 8 weeks after the result. The final response rate was 93.7%. Predictors of anxiety at each phase were assessed using multiple regression. RESULTS:Among those screening negative (94.7%), anxiety at screening was very low and remained so during the screening process. Among those screening false positive, anxiety was significantly higher 8 weeks after having received a negative diagnosis. Predictors of anxiety before screening were lower education and higher age, with a strong exogenous anxiety component. For subsequent phases, the initial anxiety score and education were the main determinants. Furthermore, a false positive result at screening was the most important predictor of anxiety 2 months after negative diagnosis. Anxiety measured with the BCA was strongly correlated with the PCQ. CONCLUSION:Anxiety was very low at screening and remained so during the process for negative women. Initial anxiety level was a strong predictor of anxiety during the entire process, up to 8 weeks after a negative result, and could be easily assessed using the BCA. The sustained higher anxiety level among those screening false positive is an undesirable side effect of the programme.
AIDS | 1999
Françoise Dubois-Arber; André Jeannin; Brenda Spencer
OBJECTIVES The Swiss Aids prevention strategy has been subject to a continuous process of evaluation for the past 12 years. This paper describes the conceptual approach, methodology, results obtained and contribution to policy-making of that evaluation. DESIGN The evaluation is on-going, global with respect to all components of the strategy, and utilization-focused. Each successive phase of the evaluation has included 10-20 studies centred either on aspects of process, of outcome or of environmental context. Findings are synthesized at the end of each phase. METHODS Both quantitative and qualitative methods are used. Studies generally have one of three functions within the overall evaluation: assessment of trends through surveys or other types of repeated studies; evaluation of specific areas through a series of studies from different viewpoints; in-depth investigation or rapid assessment through one-off studies. Various methods of triangulation are used to validate findings. RESULTS The evaluation has allowed for: the observation of behavioural change in different populations; the availability of scientific data in controversial fields such as drug-use policy; an understanding of the diversity of public appropriation of prevention messages. Recommendations are regularly formulated and have been used by policy-makers and field workers for strategy development. CONCLUSIONS The global approach adopted corresponds well to the evaluation requirements of an integrated long-term prevention strategy. Cost is low relative to the extent of information provided. Such an evaluation cannot however address the question of causal relationship between the strategy and observed changes. The evaluation has contributed to the development of a culture of evaluation in Swiss AIDS prevention more generally.
International Journal of Eating Disorders | 1998
Corinne Devaud; André Jeannin; Françoise Narring; Christine Ferron; Pierre-André Michaud
OBJECTIVES To measure the prevalence of eating disorders in a national representative sample of adolescent girls and association of eating disorders with other behavioral/mental problems in Switzerland. METHODS As part of a national health survey, a subsample of 1,084 15 to 20-year-old female students attending school aged filled in a self-administered anonymous questionnaire focusing on eating behavior and body image. Factor analysis made on these specific questions reveals two major dimensions: weight and image concern (WIC) and problematic eating conduct (PEC). The correlates of these two dimensions were measured using bivariate analyses. RESULTS Among girls, 62% say they want to lose weight, 36% feel too fat, 37% report fasting episodes, 18.9% fear not to be able to stop eating, 9.1% engage in binge eating at least once a week (1.9% daily), 1.6% self-induced vomit at least once a week (0.2% daily). Girls who exhibit high WIC (N = 198) or high PEC (N = 75) scores report significantly more mood problems (p < .05), suicidal conducts (p < .05), or violent and aggressive behaviors (p < .05). No association is found with substance use. Associations with acting-out behavior are stronger among high PEC subjects, whereas those with mood disorders are stronger among high WIC subjects. CONCLUSION A large proportion of adolescent girls show concerns regarding their weight and body image whereas a less important proportion exhibit dysfunctional eating behavior. The results confirm the associations between eating disorder and mood, suicide, and conduct problems but infirm the association with substance use. Girls who exhibit problematic conducts appear to require more attention from health resources.
Journal of Acquired Immune Deficiency Syndromes | 2010
Hugues Balthasar; André Jeannin; Stéphanie Lociciro; Françoise Dubois-Arber
Objective:To identify prevalence of and factors associated with intentional use of HIV risk reduction practices by men who have sex with men during anal intercourse with casual partners. Methods:Cross-sectional survey pertaining to the Swiss HIV behavioral surveillance system, using an anonymous self-administered questionnaire in a self-selected sample of men who have sex with men (n = 2953). Multinomial regression was used to estimate factors associated with reporting either “no or inconsistent condom use” or “one or more risk reduction practices” over “consistent condom use.” Results:57.2% reported anal intercourse with casual partner(s) over the last 12 months. Of these, 24.0% declared having used a risk reduction practice (73.8% of those who did not use condoms consistently). HIV-positive people were more likely to have done so. Most predictors were similarly associated to both regression categories. Four significant predictors were common to both regression categories: Internet partner seeking, age, age squared, and the interaction between HIV status positive and number of partners. The only association that differed markedly between the 2 regression categories was having a number of partners above median, significantly associated with the risk reduction category. Conclusions:Although condom use is the most frequent protection strategy in anal intercourse with casual partners, risk reduction practices are highly prevalent. However, there are no clear differences regarding predictors between risk reduction practices and inconsistent or no condom use. This suggests that risk reduction is an opportunistic response rather than a strategy per se.
BMC Infectious Diseases | 2010
Françoise Dubois-Arber; André Jeannin; Brenda Spencer; Jean-Pierre Gervasoni; Bertrand Graz; Jonathan Elford; Vivian Hope; Helen Ward; Mary Haour-Knipe; Nicola Low; Marita van de Laar
BackgroundUsed in conjunction with biological surveillance, behavioural surveillance provides data allowing for a more precise definition of HIV/STI prevention strategies. In 2008, mapping of behavioural surveillance in EU/EFTA countries was performed on behalf of the European Centre for Disease prevention and Control.MethodNine questionnaires were sent to all 31 member States and EEE/EFTA countries requesting data on the overall behavioural and second generation surveillance system and on surveillance in the general population, youth, men having sex with men (MSM), injecting drug users (IDU), sex workers (SW), migrants, people living with HIV/AIDS (PLWHA), and sexually transmitted infection (STI) clinics patients. Requested data included information on system organisation (e.g. sustainability, funding, institutionalisation), topics covered in surveys and main indicators.ResultsTwenty-eight of the 31 countries contacted supplied data. Sixteen countries reported an established behavioural surveillance system, and 13 a second generation surveillance system (combination of biological surveillance of HIV/AIDS and STI with behavioural surveillance). There were wide differences as regards the year of survey initiation, number of populations surveyed, data collection methods used, organisation of surveillance and coordination with biological surveillance. The populations most regularly surveyed are the general population, youth, MSM and IDU. SW, patients of STI clinics and PLWHA are surveyed less regularly and in only a small number of countries, and few countries have undertaken behavioural surveys among migrant or ethnic minorities populations. In many cases, the identification of populations with risk behaviour and the selection of populations to be included in a BS system have not been formally conducted, or are incomplete. Topics most frequently covered are similar across countries, although many different indicators are used. In most countries, sustainability of surveillance systems is not assured.ConclusionAlthough many European countries have established behavioural surveillance systems, there is little harmonisation as regards the methods and indicators adopted. The main challenge now faced is to build and maintain organised and functional behavioural and second generation surveillance systems across Europe, to increase collaboration, to promote robust, sustainable and cost-effective data collection methods, and to harmonise indicators.
Journal of Adolescent Health | 2008
Dagmar M. Haller; Pierre-André Michaud; Joan-Carles Suris; André Jeannin; Françoise Narring
Data from studies in the United States suggest that young people engaging in health-compromising behaviors have lower access to health care. Using data from a Swiss national survey we tested the hypothesis that in a country with universal insurance coverage, adolescents engaging in health-compromising behaviors access primary care to the same extent as those who do not engage in these behaviors.