title: HIV-1 diversity and prevalence differ between urban and rural areas in the Mbeya region of Tanzania.
abstract: OBJECTIVE
  To characterize HIV-1 strains in a potential vaccine trial cohort (CODE) in the Mbeya region of southwest Tanzania.
  
  
  METHODS
  Study volunteers (n = 3096) were recruited from urban areas in Mbeya Town, using two different recruitment strategies, and in a nearby rural village.
  
  
  METHODS
  Cryopreserved plasma from 507 HIV-1 prevalent cases was the source of viral RNA for HIV-1 genotyping by the Multi-region Hybridization Assay, the MHA(acd), and selected strains were confirmed by complete genome sequencing.
  
  
  RESULTS
  The overall HIV-1 prevalence was 16.6% [95% confidence interval (CI), 15.3-17.9] within the cohort. HIV-1 prevalence was higher among women, and in urban areas. Recruitment through advertisement targeted a high-risk urban male population for HIV-1 infection [adjusted odds ratio (adj. OR), 1.68; 95% CI, 1.13-2.51] when compared with men recruited door-to-door. The complexity of the HIV-1 epidemic was also higher in urban areas evidenced by the high-risk of HIV-1 infection with a recombinant strain (adj. OR, 2.69; 95% CI, 1.08-6.69) and HIV-1 dual infection (adj. OR, 5.16; 95% CI, 1.07-24.9), mainly driven by urban men recruited through advertisement.
  
  
  CONCLUSIONS
  Overall the urban epidemic was more genetically complex, with higher prevalence and more recombinants and dual infections. Vaccine trials in Mbeya region can assess a complex HIV-1 population dynamic and determine vaccine efficacy in relationship to the genetic diversity of HIV-1 strains that challenge vaccines.
authors.affiliation: US Military HIV Research Program (USMHRP), Walter Reed Army Institute of Research, Division of Retrovirology, 1600 East Gude Drive, Silver Spring, MD 20850, USA. marroyo@hivresearch.org
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Arroyo
authors.forename: Michael
authors.initials: M
authors.lastname: Hoelscher
authors.forename: Warren
authors.initials: W
authors.lastname: Sateren
authors.forename: Eleuter
authors.initials: E
authors.lastname: Samky
authors.forename: Leonard
authors.initials: L
authors.lastname: Maboko
authors.forename: Oliver
authors.initials: O
authors.lastname: Hoffmann
authors.forename: Gustavo
authors.initials: G
authors.lastname: Kijak
authors.forename: Merlin
authors.initials: M
authors.lastname: Robb
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Birx
authors.forename: Francine E
authors.initials: FE
authors.lastname: McCutchan
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D015658:HIV Infections / Q000145:classification / Q000453:epidemiology*; D015497:HIV-1 / Q000145:classification*; D006801:Humans; D008297:Male; D016017:Odds Ratio; D015995:Prevalence; D012423:Rural Health; D013636:Tanzania / Q000453:epidemiology; D014504:Urban Health