title: Swaziland HIV Incidence Measurement Survey (SHIMS): a prospective national cohort study.
abstract: Swaziland has the highest national HIV prevalence worldwide. The Swaziland HIV Incidence Measurement Survey (SHIMS) provides the first national HIV incidence estimate based on prospectively observed HIV seroconversions.
  
  
  
  A two-stage survey sampling design was used to select a nationally representative sample of men and women aged 18-49 years from 14 891 households in 575 enumeration areas in Swaziland, who underwent household-based counselling and rapid HIV testing during 2011. All individuals aged 18-49 years who resided or had slept in the household the night before and were willing to undergo home-based HIV testing, answer demographic and behavioural questions in English or siSwati, and provide written informed consent were eligible for the study. We performed rapid HIV testing and assessed sociodemographic and behavioural characteristics with use of a questionnaire at baseline and, for HIV-seronegative individuals, 6 months later. We calculated HIV incidence with Poisson regression modelling as events per person-years × 100, and we assessed covariables as predictors with Cox proportional hazards modelling. Survey weighting was applied and all models used survey sampling methods.
  
  
  
  Between Dec 10, 2010, and June 25, 2011, 11 897 HIV-seronegative adults were enrolled in SHIMS and 11 232 (94%) were re-tested. Of these, 145 HIV seroconversions were observed, resulting in a weighted HIV incidence of 2·4% (95% CI 2·1-2·8). Incidence was nearly twice as high in women (3·1%; 95% CI 2·6-3·7) as in men (1·7%; 1·3-2·1, p<0·0001). Among men, partner's HIV-positive status (adjusted hazard ratio [aHR] 2·67, 1·06-6·82, p=0·040) or unknown serostatus (aHR 4·64, 2·32-9·27, p<0·0001) in the past 6 months predicted HIV seroconversion. Among women, significant predictors included not being married (aHR 2·90, 1·44-5·84, p=0·0030), having a spouse who lives elsewhere (aHR 2·66, 1·29-5·45, p=0·0078), and having a partner in the past 6 months with unknown HIV status (aHR 2·87, 1·44-5·84, p=0·0030).
  
  
  
  Swaziland has the highest national HIV incidence in the world. In high-prevalence countries, population-based incidence measures and programmes that further expand HIV testing and support disclosure of HIV status are needed.
  
  
  
  President's Emergency Plan for AIDS Relief (PEPFAR) by the Centers for Disease Control and Prevention.
authors.affiliation: ICAP at Columbia University, Mailman School of Public Health, Columbia University, New York, NY, USA. Electronic address: jj2158@columbia.edu.
authors.forename: Jessica
authors.initials: J
authors.lastname: Justman
authors.affiliation: Jhpiego, Washington, DC, USA.
authors.forename: Jason B
authors.initials: JB
authors.lastname: Reed
authors.affiliation: US Centers for Disease Control and Prevention, Center for Global Health, Division of Global HIV/AIDS, Atlanta, GA, USA.
authors.forename: George
authors.initials: G
authors.lastname: Bicego
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
authors.forename: Deborah
authors.initials: D
authors.lastname: Donnell
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
authors.forename: Keala
authors.initials: K
authors.lastname: Li
authors.affiliation: US Centers for Disease Control and Prevention, Center for Global Health, Division of Global HIV/AIDS, Atlanta, GA, USA.
authors.forename: Naomi
authors.initials: N
authors.lastname: Bock
authors.affiliation: Pact, Dar es Salaam, Tanzania.
authors.forename: Alison
authors.initials: A
authors.lastname: Koler
authors.affiliation: ICAP at Columbia University, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Neena M
authors.initials: NM
authors.lastname: Philip
authors.affiliation: Clinton Health Access Initiative, Mbabane, Swaziland.
authors.forename: Charmaine K
authors.initials: CK
authors.lastname: Mlambo
authors.affiliation: US Centers for Disease Control and Prevention, Center for Global Health, Division of Global HIV/AIDS, Atlanta, GA, USA.
authors.forename: Bharat S
authors.initials: BS
authors.lastname: Parekh
authors.affiliation: ICAP at Columbia University, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Yen T
authors.initials: YT
authors.lastname: Duong
authors.affiliation: US Centers for Disease Control and Prevention, Center for Global Health, Division of Global HIV/AIDS, Atlanta, GA, USA.
authors.forename: Dennis L
authors.initials: DL
authors.lastname: Ellenberger
authors.affiliation: ICAP at Columbia University, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Wafaa M
authors.initials: WM
authors.lastname: El-Sadr
authors.affiliation: Ministry of Health-Swaziland, Mbabane, Swaziland.
authors.forename: Rejoice
authors.initials: R
authors.lastname: Nkambule
mesh_terms: D000293:Adolescent; D000328:Adult; D003376:Counseling; D013541:Eswatini / Q000453:epidemiology; D005191:Family Characteristics; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology* / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D015994:Incidence; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D015995:Prevalence; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D012731:Sex Counseling; D011795:Surveys and Questionnaires; D055815:Young Adult