title: Factors Associated with Variations in Population HIV Prevalence across West Africa: Findings from an Ecological Analysis.
abstract: BACKGROUND
  Population HIV prevalence across West Africa varies substantially. We assess the national epidemiological and behavioural factors associated with this.
  
  
  METHODS
  National, urban and rural data on HIV prevalence, the percentage of younger (15-24) and older (25-49) women and men reporting multiple (2+) partners in the past year, HIV prevalence among female sex workers (FSWs), men who have bought sex in the past year (clients), and ART coverage, were compiled for 13 countries. An Ecological analysis using linear regression assessed which factors are associated with national variations in population female and male HIV prevalence, and with each other.
  
  
  RESULTS
  National population HIV prevalence varies between 0 4-2 9% for men and 0 4-5.6% for women. ART coverage ranges from 6-23%. National variations in HIV prevalence are not shown to be associated with variations in HIV prevalence among FSWs or clients. Instead they are associated with variations in the percentage of younger and older males and females reporting multiple partners. HIV prevalence is weakly negatively associated with ART coverage, implying it is not increased survival that is the cause of variations in HIV prevalence. FSWs and younger female HIV prevalence are associated with client population sizes, especially older men. Younger female HIV prevalence is strongly associated with older male and female HIV prevalence.
  
  
  CONCLUSIONS
  In West Africa, population HIV prevalence is not significantly higher in countries with high FSW HIV prevalence. Our analysis suggests, higher prevalence occurs where more men buy sex, and where a higher percentage of younger women, and older men and women have multiple partnerships. If a sexual network between clients and young females exists, clients may potentially bridge infection to younger females. HIV prevention should focus both on commercial sex and transmission between clients and younger females with multiple partners.
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Holly J
authors.initials: HJ
authors.lastname: Prudden
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Tara S
authors.initials: TS
authors.lastname: Beattie
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Natalia
authors.initials: N
authors.lastname: Bobrova
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Jasmina
authors.initials: J
authors.lastname: Panovska-Griffiths
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Zindoga
authors.initials: Z
authors.lastname: Mukandavire
authors.affiliation: The World Bank, Washington, District of Columbia, United States of America.
authors.forename: Marelize
authors.initials: M
authors.lastname: Gorgens
authors.affiliation: The World Bank, Washington, District of Columbia, United States of America.
authors.forename: David
authors.initials: D
authors.lastname: Wilson
authors.affiliation: Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Charlotte H
authors.initials: CH
authors.lastname: Watts
mesh_terms: D000293:Adolescent; D000328:Adult; D000354:Africa, Western / Q000453:epidemiology; D000367:Age Factors; D005260:Female; D015658:HIV Infections / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D060386:Sex Workers; D012725:Sexual Behavior