Démographe, Chargé de Recherche, IRD.
Équipe de recherche : Équipe 1 - Genre et Santé
Affectation géographique et adresse :
Africa Center for Health and Population Studies
P.O. Box 198
Mtubatuba 3935, South Africa
Courriel : joseph.larmarange chez ceped.org
Téléphone mobile : +27 35 550 7500
Téléphone (Africa Center) : +27 35 550 7500
Fax (Africa Center) : +27 35 550 7565
Site web personnel : http://joseph.larmarange.net
Recherches (en cours)
Champs de recherche : VIH/Sida, comportements sexuels, dépistage, prévention, pauvreté, composition des ménages, structures de consommation.
Programme(s) de recherche :
Zones géographiques étudiées : Afrique subsaharienne, UEMOA, KwaZulu-Natal (Afrique du Sud).
Animations scientifiques
Publications récentes
2011 |
Larmarange, Joseph, Roselyne Vallo, Seydou Yaro, Philippe Msellati, and Nicolas Méda. "Méthodes pour cartographier les tendances régionales de la prévalence du VIH à partir des enquêtes démographiques et de santé (EDS)." Cybergeo : European Journal of Geography, no. 539 (2011): 27. http://dx.doi.org/10.4000/cybergeo.23782 (accessed February 5, 2012).
Résumé : Pour de nombreux pays, en particulier en Afrique subsaharienne, les Enquêtes Démographiques et de Santé (EDS) constituent la principale estimation de la prévalence du VIH au niveau national et en population générale. Plusieurs EDS collectent la longitude et la latitude des grappes enquêtées.Dans cet article, nous présentons trois approches méthodologiques pour cartographier les variations spatiales de la prévalence du VIH à partir des EDS. Ces approches sont appliquées à des simulations d’EDS échantillonnées à partir d’un pays modèle. Les surfaces estimées sont alors comparées à la surface initiale du modèle.Nous montrons qu’une méthode utilisant des estimateurs à noyau à fenêtres adaptatives de même effectif permet d’estimer les principales tendances régionales des épidémies. Son application aux données de l’EDS 2003 du Burkina Faso fournit une image plausible de la situation épidémiologique dans ce pays.
For many countries, in particular in sub-Saharan Africa, Demographic and Health Surveys (DHS) are the main estimates of HIV prevalence at national level in general population. Several DHS collect longitude and latitude of surveyed clusters.In this paper, we present three methodological approaches for mapping spatial variations of HIV prevalence from DHS. These approaches are applied to DHS simulation sampled from a model country. The estimated surfaces are then compared with the initial surface of the model.We show that a method using kernel estimators with adaptive bandwidths of the same number of observed people allows estimating main regional trends of the epidemics. Its application to data from 2003 DHS of Burkina Faso give a plausible picture of the epidemiological situation in this country.
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Larmarange, Joseph, Roselyne Vallo, Seydou Yaro, Philippe Msellati, and Nicolas Méda. "Methods for mapping regional trends of HIV prevalence from Demographic and Health Surveys (DHS)." Cybergeo : European Journal of Geography 558 (2011).
Résumé : In many countries, particularly in sub-Saharan Africa, Demographic and Health Surveys (DHSs) are the main way of estimating HIV prevalence nationally in the general population. Some DHSs record the longitude and latitude of the survey clusters. We present three methodological approaches for mapping spatial variations in HIV prevalence using the DHSs. These approaches are applied to simulated DHS samplings from a model country. The estimated surfaces are then compared with the model’s initial surface. We demonstrate that a method using kernel estimators with adaptive bandwidths size of equal number of persons observed can be used to estimate the main regional trends in epidemics. Application to Burkina Faso’s 2003 DHS data provides a plausible image of that country’s epidemiological situation.
Mots-Clés : demographic and health surveys; Developing Countries; enquêtes démographiques et de santé; HIV; interpolation; interpolation par noyaux; kernel interpolation; méthodologie; methodology; pays en développement; regional trends; tendances régionales; VIH
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2010 |
Henry, Emile, Fabienne Marcellin, Yves Yomb, Lionel Fugon, Steave Nemande, Charles Gueboguo, Joseph Larmarange, Fred Emmanuel Eboko Trenado, and Bruno Spire. "Factors associated with unprotected anal intercourse among men who have sex with men in Douala, Cameroon." Sexually Transmitted Infections 86, no. 2 (2010): 136–140.
Résumé : Objectives Research on men who have sex with men (MSM) in sub-Saharan Africa was neglected for a long time. The objective of this study was to understand factors associated with unprotected anal intercourse (UAI) with male partners among a group of MSM living in the city of Douala, Cameroon. Methods In 2008, a survey on the sexual activity and practices of MSM was set up in Douala in collaboration with a local community-based organisation. Data were collected among a convenience sample of 168 MSM during face-to-face interviews with trained interviewers. Results A total of 142 individuals reported sexual activity during the previous 6 months, among whom 80 (57%) reported UAI with male partners. In a multivariate logistic regression model adjusted for the frequency of sexual intercourse, not having had access to prevention interventions and not knowing any HIV-infected person were both independently associated with a higher risk of UAI. Other factors associated with this higher risk included having had a stable male partnership at some point in one's life and not having been out of Douala for more than 4 weeks during the previous year. Conclusions This community-based research is the first study of MSM in Cameroon and the HIV transmission risks they face. Results show the importance of HIV prevention interventions from peers, and underline the need to maintain efforts to develop specific interventions targeting MSM more efficiently in the African context.
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Larmarange, Joseph, Abdoulaye S. Wade, Abdou K. Diop, Oulimata Diop, Khady Gueye, Adama Marra, Annabel Desgrées du Loû, and for ELIHoS Group. "Men Who Have Sex with Men (MSM) and Factors Associated with Not Using a Condom at Last Sexual Intercourse with a Man and with a Woman in Senegal." PLoS ONE 5, no. 10 (2010): e13189.
Résumé : Background
Men who have sex with other men (MSM) are a vulnerable population in Africa that has been insufficiently explored. Given the high rate of bisexuality among MSM (73% in the past year), it is important to understand their risk-taking behaviors regarding both men and women.
Methodology/Principal Findings
A socio-behavioral survey was carried out in 2007 among 501 MSM recruited using the snowball sampling method. We explore in this article why a condom was not used during last sexual intercourse with a man and with a woman, taking into account the respondent's characteristics, type of relationship and the context of the sexual act. In the survey, 489 men reported that they had had sexual intercourse at least once with another man during the previous year, and 358 with a man and with a woman. The main risk factors for not using a condom at last sexual intercourse with another man were having sex in a public place (aOR = 6.26 [95%CI: 2.71–14.46]), non-participation in an MSM prevention program (aOR = 3.47 [95%CI: 2.12–5.69]), a 19 years old or younger partner (aOR = 2.6 [95%CI: 1.23–4.53]), being 24 years or younger (aOR = 2.07 [95%CI: 1.20–3.58]) or being 35 years or over (aOR = 3.08 [95%CI:1.11–8.53]) and being unemployed (aOR = 0.36 [95%CI: 0.10–1.25]). The last sexual intercourse with the respondent's wife was hardly ever protected (2%). With women, the other factors were a 15 years or younger partner (aOR = 6.45 [95%CI: 2.56–16.28]), being educated (primary: aOR = 0.45 [95%CI: 0.21–0.95], secondary or higher: aOR = 0.26 [95%CI: 0.11–0.62]), being a student (aOR = 2.20 [95%CI: 1.07–4.54]) or unemployed (aOR = 3.72 [95%CI: 1.31–10.61]) and having participated in a MSM prevention program (aOR = 0.57 [95%CI: 0.34–0.93]).
Conclusion
Having participated in a prevention program specifically targeting MSM constitutes a major prevention factor. However, these programs targeting MSM must address their heterosexual practices and the specific risks involved.
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Wade, Abdoulaye S., Joseph Larmarange, Abdou K. Diop, Oulimata Diop, Khady Gueye, Adama Marra, Amsata Sene, Catherine Enel, Pape Niang Diallo, Ndeye Coumba Toure Kane et al. "Reduction in risk-taking behaviors among MSM in Senegal between 2004 and 2007 and prevalence of HIV and other STIs. ELIHoS Project, ANRS 12139." AIDS Care 22, no. 4 (2010): 409–414.
Résumé : An epidemiological survey conducted in Senegal in 2004 among men having sex with men (MSM) revealed high HIV prevalence and a high rate of risky behaviors within this population. Consequently, several prevention campaigns targeting MSM were implemented. A second survey was carried out in 2007 to assess the impact of these measures. This paper aims to examine trends in HIV and STI prevalence and in sexual behaviors between 2004 and 2007. The two surveys were conducted in four urban sites among 440 and 501 MSM – recruited using the snowball sampling method – in 2004 and 2007, respectively. A similar methodology was applied for both surveys. This consisted of a closed-ended questionnaire concerning socio-demographic, behavioral, and biomedical information plus a clinical examination including urine and blood tests to detect STIs and HIV infection. Between 2004 and 2007, the frequency of different sexual practices reported by MSM remained stable, but condom use for each type of sexual practice rose. The percentage of men who reported consistent condom use during previous-month anal sex has increased by about 35% (p<0.01). The percentage of men who reported consistent condom use during previous-month non-commercial sex with women has increased by 14% (p<0.01). HIV prevalence remained stable from 22.4% [95% CI: 18.6-26.8] in 2004 to 21.8% [95% CI: 18.3-25.7] in 2007 (adjusted OR = 1.05, p=0.8). Gonorrhea prevalence decreased from 5.5% [95% CI: 3.6-8.3] in 2004 to 2.6% [95% CI: 1.5-4.5] in 2007 (adjusted OR = 0.5, p=0.07). The prevention campaigns, STI and HIV care and support programs conducted in Senegal among MSM have been followed by a reduction of risk-taking behaviors and STI prevalence among this population. Specific targeting of this group within HIV/STI prevention programs seems to be effective in decreasing sexual infections.
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Voir toutes ses publications.
Encadrements pédagogiques, enseignements et administration de la recherche et/ou de l’enseignement universitaire (en cours)
Expertises et évaluations
- Relecture d’articles (pour Aids Care, Revue d’Épidémiologie et de santé publique, Santé publique, Sahara).
Projet achevé
RSS 2.0