title: Evaluation of NucliSens EasyQ HIV-1 assay for quantification of HIV-1 subtypes prevalent in South-east Asia.
abstract: BACKGROUND
  Monitoring anti-retroviral therapy requires that viral load assays for human immunodeficiency virus type 1 (HIV-1) be applicable to diverse HIV-1 subtypes.
  
  
  OBJECTIVE
  To evaluate NucliSens EasyQ HIV-1 assay for quantitation of common HIV-1 subtypes prevalent in South-east Asia.
  
  
  METHODS
  One hundred and nineteen plasma samples collected in Hong Kong and Cambodia were used to compare the performance of NucliSens EasyQ HIV-1 and COBAS Amplicor HIV-1 Monitor version 1.5 assays. Viral RNA extracted from the NucliSens MiniMAG was also used for HIV-1 subtyping.
  
  
  RESULTS
  Performance of NucliSens EasyQ correlated well with COBAS Amplicor (r=0.777, p<0.001) and the small mean difference (0.0462log(10)IU/mL) obtained in the Bland and Altman model indicated good agreement between two assays. The NucliSens EasyQ assay demonstrated a 95% sensitivity at 500IU/mL and 100% specificity. Reproducibility of this assay was within log(10)2-4IU/mL and had a coefficient of variation between 2.3% and 10.4%. Among the 109 specimens included in the analysis, HIV-1 subtyping identified 64 CRF01_AE, 38 subtype B, 3 subtype C, 3 CRF07_BC and 1 subtype G viruses.
  
  
  CONCLUSIONS
  Performance of NucliSens EasyQ was comparable to COBAS Amplicor for HIV-1 viral load monitoring. RNA extracts from NucliSens MiniMAG could be used for HIV-1 viral load monitoring, subtyping and drug resistance mutations detection. Our findings highlight the versatility of both NucliSens EasyQ and COBAS Amplicor in monitoring prevalent subtypes and rare circulating recombinant forms (CRFs) in the South-east Asia region.
authors.affiliation: Department of Microbiology, Queen Mary Hospital, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: H Y
authors.initials: HY
authors.lastname: Lam
authors.forename: J H K
authors.initials: JH
authors.lastname: Chen
authors.forename: K H
authors.initials: KH
authors.lastname: Wong
authors.forename: K
authors.initials: K
authors.lastname: Chan
authors.forename: P
authors.initials: P
authors.lastname: Li
authors.forename: M P
authors.initials: MP
authors.lastname: Lee
authors.forename: D N
authors.initials: DN
authors.lastname: Tsang
authors.forename: K Y
authors.initials: KY
authors.lastname: Yuen
authors.forename: W C
authors.initials: WC
authors.lastname: Yam
mesh_terms: D002160:Cambodia; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006723:Hong Kong; D006801:Humans; D012367:RNA, Viral / Q000235:genetics; D011897:Random Allocation; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019562:Viral Load
chemical_list: D012367:RNA, Viral; D011933:Reagent Kits, Diagnostic