title: Sexual partner characteristics and incident rectalNeisseria gonorrhoeaeandChlamydia trachomatisinfections among gay men and other men who have sex with men (MSM): a prospective cohort in Abuja and Lagos, Nigeria.
abstract: STIs includingNeisseria gonorrhoeae(NG) andChlamydia trachomatis(CT) potentiate HIV acquisition and transmission especially among gay men and other men who have sex with men (MSM). We investigated the influence of sexual network composition on incident rectal NG and/or CT infections among Nigerian MSM.
  
  
  
  TRUST/RV368 is a cohort of MSM recruited using respondent-driven sampling at trusted community centres in Abuja and Lagos, Nigeria. MSM respondents (egos) provided STI risk factors and demographic information for up to five of their most recent sexual partners (alters) within their sexual networks. Egos were tested for HIV, NG and CT every 3 months. Log-binomial regression was used to assess associations between alter characteristics and incident NG and/or CT.
  
  
  
  Between March 2013 and October 2015, 492 MSM were longitudinally screened for STIs, of which 28.0% (n=138) were positive for incident rectal STI (61 NG only, 42 CT only and 35 NG and CT). Among egos, condom use was associated with STIs (half of the time vs never (adjusted risk ratio (aRR) 0.5; 95% CI 0.3 to 0.8), always/almost always vs never (aRR 0.7; 95% CI 0.5 to 1.0)). Incident STIs were associated with having a younger alter ≤19 versus 30 years (aRR 0.6; 95% CI 0.4 to 1.0), HIV infection (aRR 1.5; 95% CI 1.1 to 2.0) and engaging in sex under the influence of alcohol (aRR 1.4 95% CI 1.1 to 1.7) among regular alters and age ≤19 versus 30 years (aRR 0.3; 95% CI 0.2 to 0.6), HIV infection (aRR 1.4; 95% CI 1.1 to 1.8) and engaging in sex under the influence of alcohol (aRR 1.2 95% CI 1.0 to 1.4) among casual alters.
  
  
  
  Given the centrality of sexual partner characteristics as risks for incident STIs among Nigerian MSM, there is a need to move beyond individual interventions and syndromic surveillance and get 'out there' in the STI management.
authors.affiliation: Institute of Human Virology University of Maryland School of Medicine, Baltimore, Maryland, USA.
authors.forename: Habib O
authors.initials: HO
authors.lastname: Ramadhani
authors.affiliation: University of Maryland School of Public Health, College Park, Maryland, USA.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Liu
authors.affiliation: Institute of Human Virology University of Maryland School of Medicine, Baltimore, Maryland, USA.
authors.forename: Rebecca G
authors.initials: RG
authors.lastname: Nowak
authors.affiliation: U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.|Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, USA.
authors.forename: Trevor A
authors.initials: TA
authors.lastname: Crowell
authors.affiliation: Institute of Human Virology Nigeria, Abuja, Federal Capital Territory, Nigeria.
authors.forename: Teclaire
authors.initials: T
authors.lastname: Ndomb
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Gaydos
authors.affiliation: U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.
authors.forename: Sheila
authors.initials: S
authors.lastname: Peel
authors.affiliation: Institute of Human Virology Nigeria, Abuja, Federal Capital Territory, Nigeria.
authors.forename: Nicaise
authors.initials: N
authors.lastname: Ndembi
authors.affiliation: Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA.
authors.forename: Stefan D
authors.initials: SD
authors.lastname: Baral
authors.affiliation: U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA.
authors.forename: Julie
authors.initials: J
authors.lastname: Ake
authors.affiliation: Institute of Human Virology University of Maryland School of Medicine, Baltimore, Maryland, USA.
authors.forename: Man E
authors.initials: ME
authors.lastname: Charurat
mesh_terms: D000328:Adult; D002690:Chlamydia Infections / Q000453:epidemiology* / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000302:isolation & purification; D015331:Cohort Studies; D019468:Disease Management; D006069:Gonorrhea / Q000453:epidemiology* / Q000382:microbiology; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission / Q000821:virology; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008875:Middle Aged; D009344:Neisseria gonorrhoeae / Q000302:isolation & purification; D009549:Nigeria / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D012002:Rectal Diseases / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D012007:Rectum / Q000382:microbiology*; D012307:Risk Factors; D012747:Sexual Partners; D012749:Sexually Transmitted Diseases / Q000453:epidemiology
keywords: CHLAMYDIA TRACHOMATIS; GAY MEN; HOMOSEXUALITY; NEISSERIA GONORRHOEA; SEXUAL NETWORKS