title: Collaborative study for the characterization of a chikungunya virus RNA reference reagent for use in nucleic acid testing.
abstract: OBJECTIVE
  Infections with the mosquito-borne chikungunya virus (CHIKV) can cause febrile illness or be asymptomatic. Laboratory diagnosis of CHIKV is often made with laboratory-developed nucleic acid amplification technology (NAT) assays because there are no U.S. Food and Drug Administration (FDA)-approved diagnostic or blood screening assays. We aimed to produce a well-characterized CHIKV RNA reference reagent (CHIKV-RR) for use in NAT assays.
  
  
  METHODS
  A CHIKV RNA-RR consisting of cell culture-grown, heat-inactivated CHIKV diluted in human plasma was assessed by 8 laboratories in a collaborative study. The participants were asked to test the CHIKV-RR using their NAT assay(s) by qualitative testing (determination of RNA end-point by testing log and half-log dilutions followed by calculation of estimated NAT-detectable units/ml, after adjustment for the sample volume used for testing), and by quantitative testing, when available.
  
  
  RESULTS
  Results from the testing showed that the CHIKV-RR had an estimated overall mean of 7.56 log10 detectable units/ml, ranging from 6.2 log10 to 8.6 log10.
  
  
  CONCLUSIONS
  The Center for Biologics for Evaluation and Research/FDA CHIKV RNA-RR for NAT was established with a concentration of 7.56 log10 detectable units/ml.
authors.affiliation: Office of Blood Research and Review, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, MD, USA.
authors.forename: G
authors.identifier: http://orcid.org/0000-0001-5361-3001
authors.initials: G
authors.lastname: Añez
authors.affiliation: Office of Biostatistics and Epidemiology, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, MD, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: Office of Blood Research and Review, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, MD, USA.
authors.forename: D A R
authors.initials: DA
authors.lastname: Heisey
authors.affiliation: Office of Blood Research and Review, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, MD, USA.
authors.forename: S
authors.initials: S
authors.lastname: Kerby
authors.affiliation: Office of Blood Research and Review, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, MD, USA.
authors.forename: M
authors.initials: M
authors.lastname: Rios
mesh_terms: D001483:Base Sequence; D002646:Chikungunya virus / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D007202:Indicators and Reagents; D025202:Molecular Diagnostic Techniques / Q000379:methods* / Q000592:standards; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques / Q000379:methods / Q000592:standards; D012367:RNA, Viral / Q000097:blood*; D012015:Reference Standards
chemical_list: D007202:Indicators and Reagents; D012367:RNA, Viral
keywords: chikungunya virus; nucleic acid amplification tests; reference standards