title: Estimating the need for antiretroviral treatment and an assessment of a simplified HIV/AIDS case definition in rural Malawi.
abstract: BACKGROUND
  Surveillance in the era of antiretroviral therapy (ART) requires estimates of HIV prevalence as well as the proportion eligible for ART. We estimated HIV prevalence and assessed field staging of individuals to estimate the burden of HIV disease needing treatment in rural Malawi.
  
  
  METHODS
  Adults aged 18-59 years in a demographic surveillance system were interviewed, examined, and HIV counselled and tested. Staging that used a simplified version of the WHO criteria ('field checklist') was compared with staging by a medical assistant using a 'clinic checklist' and to CD4 cell results.
  
  
  RESULTS
  A total of 2129 of 2303 eligible adults (92.4%) were traced, and 2047 (96.1%) participated. Of the 1443 participants (70.5%) tested, 11.6% were HIV positive. ART eligibility classification by the field and clinic checklists were concordant in 122 of 133 HIV-positive individuals. Compared with the clinic checklist, the field checklist had a sensitivity of 50% and a specificity of 96%. Including those already known to be on ART, staging by the field and clinic checklists estimated ART eligibility at 16.3 and 17.7% of HIV-positive individuals, respectively. Using CD4 cell count under 250 cells/mul or WHO stage III/IV, the Malawi national programme criteria, 38% of HIV-positive individuals were eligible for ART, compared with 31% based on the 2006 WHO criteria of CD4 cell count under 200 cells/mul or WHO stage IV or CD4 cell count of 200-350 cells/mul and WHO stage III.
  
  
  CONCLUSIONS
  The field checklist was not a suitable tool for individual staging. Criteria for ART eligibility based on clinical staging alone missed two-thirds of those eligible by clinical staging and CD4 cell count.
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK. nuala.mcgrath@lshtm.ac.uk
authors.forename: Nuala
authors.initials: N
authors.lastname: McGrath
authors.forename: Katharina
authors.initials: K
authors.lastname: Kranzer
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Saul
authors.forename: Amelia C
authors.initials: AC
authors.lastname: Crampin
authors.forename: Simon
authors.initials: S
authors.lastname: Malema
authors.forename: Lackson
authors.initials: L
authors.lastname: Kachiwanda
authors.forename: Basia
authors.initials: B
authors.lastname: Zaba
authors.forename: Andreas
authors.initials: A
authors.lastname: Jahn
authors.forename: Paul Em
authors.initials: PE
authors.lastname: Fine
authors.forename: Judith R
authors.initials: JR
authors.lastname: Glynn
mesh_terms: D000293:Adolescent; D000328:Adult; D044966:Anti-Retroviral Agents / Q000600:supply & distribution* / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count / Q000706:statistics & numerical data; D004608:Eligibility Determination / Q000379:methods; D004812:Epidemiologic Methods; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006301:Health Services Needs and Demand; D006801:Humans; D008295:Malawi / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012423:Rural Health
chemical_list: D044966:Anti-Retroviral Agents