title: Social meets molecular: Combining phylogenetic and latent class analyses to understand HIV-1 transmission in Switzerland.
abstract: Switzerland has a complex human immunodeficiency virus (HIV) epidemic involving several populations. We examined transmission of HIV type 1 (HIV-1) in a national cohort study. Latent class analysis was used to identify socioeconomic and behavioral groups among 6,027 patients enrolled in the Swiss HIV Cohort Study between 2000 and 2011. Phylogenetic analysis of sequence data, available for 4,013 patients, was used to identify transmission clusters. Concordance between sociobehavioral groups and transmission clusters was assessed in correlation and multiple correspondence analyses. A total of 2,696 patients were infected with subtype B, 203 with subtype C, 196 with subtype A, and 733 with recombinant subtypes (mainly CRF02_AG and CRF01_AE). Latent class analysis identified 8 patient groups. Most transmission clusters of subtype B were shared between groups of gay men (groups 1-3) or between the heterosexual groups "heterosexual people of lower socioeconomic position" (group 4) and "injection drug users" (group 8). Clusters linking homosexual and heterosexual groups were associated with "older heterosexual and gay people on welfare" (group 5). "Migrant women in heterosexual partnerships" (group 6) and "heterosexual migrants on welfare" (group 7) shared non-B clusters with groups 4 and 5. Combining approaches from social and molecular epidemiology can provide insights into HIV-1 transmission and inform the design of prevention strategies.
authors.forename: Dorita
authors.initials: D
authors.lastname: Avila
authors.forename: Olivia
authors.initials: O
authors.lastname: Keiser
authors.forename: Matthias
authors.initials: M
authors.lastname: Egger
authors.forename: Roger
authors.initials: R
authors.lastname: Kouyos
authors.forename: Jürg
authors.initials: J
authors.lastname: Böni
authors.forename: Sabine
authors.initials: S
authors.lastname: Yerly
authors.forename: Thomas
authors.initials: T
authors.lastname: Klimkait
authors.forename: Pietro L
authors.initials: PL
authors.lastname: Vernazza
authors.forename: Vincent
authors.initials: V
authors.lastname: Aubert
authors.forename: Andri
authors.initials: A
authors.lastname: Rauch
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bonhoeffer
authors.forename: Huldrych F
authors.initials: HF
authors.lastname: Günthard
authors.forename: Tanja
authors.initials: T
authors.lastname: Stadler
authors.forename: Ben D
authors.initials: BD
authors.lastname: Spycher
mesh_terms: D000328:Adult; D005260:Female; D015658:HIV Infections / Q000635:transmission* / Q000821:virology; D015497:HIV-1 / Q000145:classification / Q000235:genetics*; D020010:Heterosexuality; D006716:Homosexuality; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D012919:Social Behavior; D012962:Sociology, Medical; D013557:Switzerland
keywords: HIV; HIV-1 transmission; Switzerland; injection drug use; latent class analysis; phylogenetics; sexual orientation; socioeconomic position