title: The effect of sample handling on cross sectional HIV incidence testing results.
abstract: OBJECTIVE
  To determine if mishandling prior to testing would make a sample from a chronically infected subject appear recently infected when tested by cross-sectional HIV incidence assays.
  
  
  METHODS
  Serum samples from 31 subjects with chronic HIV infection were tested. Samples were subjected to different handling conditions, including incubation at 4 °C, 25 °C and 37 °C, for 1, 3, 7 or 15 days prior to testing. Samples were also subjected to 1,3, 7 and 15 freeze-thaw cycles prior to testing. Samples were tested using the BED capture enzyme immuno assay (BED-CEIA), Vironostika-less sensitive (V-LS), and an avidity assay using the Genetic Systems HIV-1/HIV-2 plus O EIA (avidity assay).
  
  
  RESULTS
  Compared to the sample that was not subjected to any mishandling conditions, for the BED-CEIA, V-LS and avidity assay, there was no significant change in test results for samples incubated at 4 °C or 25 °C prior to testing. No impact on test results occurred after 15 freeze-thaw cycles. A decrease in assay results was observed when samples were held for 3 days or longer at 37 °C prior to testing.
  
  
  CONCLUSIONS
  Samples can be subjected up to 15 freeze-thaw cycles without affecting the results the BED-CEIA, Vironostika-LS, or avidity assays. Storing samples at 4 °C or 25 °C for up to fifteen days prior to testing had no impact on test results. However, storing samples at 37°C for three or more days did affect results obtained with these assays.
authors: Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Baltimore, Maryland, United States of America. olaeyen1@jhmi.edu
authors: Oliver
authors: O
authors: Laeyendecker
authors: Amanda
authors: A
authors: Latimore
authors: Susan H
authors: SH
authors: Eshleman
authors: Jean
authors: J
authors: Summerton
authors: Amy E
authors: AE
authors: Oliver
authors: Jordyn
authors: J
authors: Gamiel
authors: Trudy
authors: T
authors: Dobbs
authors: Joanne
authors: J
authors: Mei
authors: Gary
authors: G
authors: Murphy
authors: John V
authors: JV
authors: Parry
authors: S Michele
authors: SM
authors: Owen
authors: Thomas C
authors: TC
authors: Quinn
mesh_terms: D015982:Bias; D001793:Blood Preservation / Q000379:methods / Q000592:standards; D003430:Cross-Sectional Studies; D015925:Cryopreservation / Q000379:methods / Q000592:standards; D003951:Diagnostic Errors / Q000706:statistics & numerical data*; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D013048:Specimen Handling / Q000379:methods / Q000592:standards*; D013696:Temperature; D013997:Time Factors