title: Age-targeted HIV treatment and primary prevention as a 'ring fence' to efficiently interrupt the age patterns of transmission in generalized epidemic settings in South Africa.
abstract: Generalized HIV epidemics propagate to future generations according to the age patterns of transmission. We hypothesized that future generations could be protected from infection using age-targeted prevention, analogous to the ring-fencing strategies used to control the spread of smallpox.
  
  
  
  We modeled age-targeted or cohort-targeted outreach with HIV treatment and/or prevention using EMOD-HIV v0·8, an individual-based network model of HIV transmission in South Africa.
  
  
  
  Targeting ages 20 to 30 with intensified outreach, linkage, and eligibility for antiretroviral therapy (ART) averted 45% as many infections as universal outreach for approximately one-fifth the cost beyond existing HIV services. Though cost-effective, targeting failed to eliminate all infections to those under 20 due to vertical and inter-generational transmission. Cost-effectiveness of optimal prevention strategies included US$6238 per infection averted targeting ages 10-30, US$5031 targeting 20-30, US$4279 targeting 22-27, and US$3967 targeting 25-27, compared to US$10 812 for full-population test-and-treat. Minimizing burden (disability-adjusted life years [DALYs]) rather than infections resulted in older target age ranges because older adults were more likely to receive a direct health benefit from treatment.
  
  
  
  Age-targeted treatment for HIV prevention is unlikely to eliminate HIV epidemics, but is an efficient strategy for reducing new infections in generalized epidemics settings.
authors.affiliation: Institute for Disease Modeling, Bellevue, WA, USA abershteyn@intven.com.
authors.forename: Anna
authors.initials: A
authors.lastname: Bershteyn
authors.affiliation: Institute for Disease Modeling, Bellevue, WA, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Klein
authors.affiliation: Institute for Disease Modeling, Bellevue, WA, USA.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Eckhoff
mesh_terms: D000328:Adult; D000367:Age Factors; D000998:Antiviral Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D003362:Cost-Benefit Analysis; D058872:Epidemics; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission*; D006801:Humans; D015994:Incidence; D008297:Male; D011322:Primary Prevention / Q000379:methods*; D013019:South Africa / Q000453:epidemiology
chemical_list: D000998:Antiviral Agents
keywords: Antiretroviral therapy; Cost-effectiveness; Epidemic modeling; HIV prevention; South Africa