title: Sustained effect of couples' HIV counselling and testing on risk reduction among Zambian HIV serodiscordant couples.
abstract: BACKGROUND
  We present temporal trends in self-reported and biological markers of unprotected sex and sex with concurrent partners in discordant couples receiving couples' voluntary HIV counselling and testing (CVCT).
  
  
  METHODS
  Heterosexual Zambian HIV-serodiscordant couples were enrolled into longitudinal follow-up in an open cohort (1994-2012). Multivariable Anderson-Gill models explored predictors of self-report and biological indicators of unprotected sex within (including sperm on a vaginal swab, incident pregnancy or incident linked HIV infection) and outside (including self-report, STI and unlinked HIV infection) the union. Measures of secular trends in baseline measures were also examined.
  
  
  RESULTS
  At enrolment of 3049 couples, men were 35 years old on average, women were 29 years, and couples had been together for an average of 7 years.M+F- couplesreported an average of 16.6 unprotected sex acts in the 3 months prior to enrolment (pre-CVCT), dropping to 5.3 in the >0-3 month interval, and 2.0 in >6 month intervals (p-trend <0.001). Corresponding values forM-F+ coupleswere 22.4 unprotected sex acts in the 3 months prior enrolment, dropping to 5.2 in the >0-3 month interval, and 3.1 in >6 month intervals (p-trend <0.001). Significant reductions in self-report and biological markers of outside partners were also noted. Predictors of unprotected sex between study partners after CVCT included prevalent pregnancy (adjusted HR, aHR=1.6-1.9); HIV+ men being circumcised (aHR=1.2); and HIV- women reporting sex with outside partners (aHR=1.3), alcohol (aHR=1.2), injectable (aHR=1.4) or oral (aHR=1.4) contraception use. Fertility intentions were also predictive of unprotected sex (aHR=1.2-1.4). Secular trends indicated steady declines in reported outside partners and STIs.
  
  
  CONCLUSIONS
  Reductions in self-reported unprotected sex after CVCT were substantial and sustained. Reinforced risk-reduction counselling in pregnant couples, couples desiring children and couples with HIV- women having outside partners or using alcohol or injectable or oral contraception are indicated.
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Department of Epidemiology, Rollins School of Public Health, Laney Graduate School, Emory University, Atlanta, Georgia, USA.
authors.forename: Kristin M
authors.initials: KM
authors.lastname: Wall
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: William
authors.initials: W
authors.lastname: Kilembe
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Department of Gynaecology and Obstetrics (BV), Internal Medicine (SL) and Surgery (RC), School of Medicine, University of Zambia, Lusaka, Zambia.
authors.forename: Bellington
authors.initials: B
authors.lastname: Vwalika
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Department of Gynaecology and Obstetrics, Emory University, School of Medicine, Atlanta, Georgia, USA.
authors.forename: Lisa B
authors.initials: LB
authors.lastname: Haddad
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Department of Gynaecology and Obstetrics (BV), Internal Medicine (SL) and Surgery (RC), School of Medicine, University of Zambia, Lusaka, Zambia.
authors.forename: Shabir
authors.initials: S
authors.lastname: Lakhi
authors.affiliation: Department of Epidemiology, Rollins School of Public Health, Laney Graduate School, Emory University, Atlanta, Georgia, USA.
authors.forename: Udodirim
authors.initials: U
authors.lastname: Onwubiko
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Naw
authors.initials: N
authors.lastname: Htee Khu
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Department of Epidemiology, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, USA.
authors.forename: Ilene
authors.initials: I
authors.lastname: Brill
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Department of Gynaecology and Obstetrics (BV), Internal Medicine (SL) and Surgery (RC), School of Medicine, University of Zambia, Lusaka, Zambia.
authors.forename: Roy
authors.initials: R
authors.lastname: Chavuma
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Cheswa
authors.initials: C
authors.lastname: Vwalika
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Lawrence
authors.initials: L
authors.lastname: Mwananyanda
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.|Ministry of Community Development, Mother and Child Health, Lusaka, Zambia.
authors.forename: Elwyn
authors.initials: E
authors.lastname: Chomba
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Mulenga
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Amanda
authors.initials: A
authors.lastname: Tichacek
authors.affiliation: Rwanda Zambia HIV Research Group, Department of Pathology and Laboratory Medicine, School of Medicine and Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Allen
mesh_terms: D000328:Adult; D017280:Condoms / Q000706:statistics & numerical data*; D003268:Contraception Behavior; D003376:Counseling / Q000379:methods; D005191:Family Characteristics; D005260:Female; D005500:Follow-Up Studies; D006679:HIV Seropositivity / Q000523:psychology*; D020010:Heterosexuality; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data; D040242:Risk Reduction Behavior; D012725:Sexual Behavior / Q000523:psychology; D012747:Sexual Partners / Q000523:psychology; D015024:Zambia
keywords: AFRICA; AIDS; BEHAVIOURAL INTERVENTIONS; EPIDEMIOLOGY (GENERAL); SEXUAL BEHAVIOUR