BACKGROUND: With the ongoing public health emergency due to Zika virus (ZIKV), nucleic acid testing (NAT) is essential for clinical diagnosis and screening of blood donors. However, NAT for ZIKV has not been standardized, and this study was performed to establish a World Health Organization (WHO) International Standard (IS) for ZIKV RNA; WHO ISs have been used to improve detection and quantification of blood-borne viruses. STUDY DESIGN AND METHODS: The candidate IS (cIS), code number 11468/16, was prepared by heat inactivation and lyophilization of a ZIKV strain isolated from a patient in French Polynesia in 2013. The cIS was evaluated together with other reference materials, including both Asian and African ZIKV lineages as well as a panel of clinical samples and in vitro-transcribed RNAs. The samples for evaluation were distributed to 24 laboratories from 11 countries. The assays used consisted of a mixture of in-house developed and commercial assays (available or in development). RESULTS: The potencies of the standards were determined by quantitative and qualitative assays. In total, 37 sets of data were analyzed: 19 from quantitative assays and 18 from qualitative assays. Data demonstrated wide variations in reported potencies of the cIS and the other study samples. CONCLUSIONS: Assay variability was substantially reduced when ZIKV RNA concentrations from the biological reference materials and clinical samples were expressed relative to the cIS. Thus, the WHO has established 11468/16 as the 1st IS for ZIKV RNA, with a unitage of 50,000,000 IU/mL.
BACKGROUND: With the ongoing public health emergency due to Zika virus (ZIKV), nucleic acid testing (NAT) is essential for clinical diagnosis and screening of blood donors. However, NAT for ZIKV has not been standardized, and this study was performed to establish a World Health Organization (WHO) International Standard (IS) for ZIKV RNA; WHO ISs have been used to improve detection and quantification of blood-borne viruses. STUDY DESIGN AND METHODS: The candidate IS (cIS), code number 11468/16, was prepared by heat inactivation and lyophilization of a ZIKV strain isolated from a patient in French Polynesia in 2013. The cIS was evaluated together with other reference materials, including both Asian and African ZIKV lineages as well as a panel of clinical samples and in vitro-transcribed RNAs. The samples for evaluation were distributed to 24 laboratories from 11 countries. The assays used consisted of a mixture of in-house developed and commercial assays (available or in development). RESULTS: The potencies of the standards were determined by quantitative and qualitative assays. In total, 37 sets of data were analyzed: 19 from quantitative assays and 18 from qualitative assays. Data demonstrated wide variations in reported potencies of the cIS and the other study samples. CONCLUSIONS: Assay variability was substantially reduced when ZIKV RNA concentrations from the biological reference materials and clinical samples were expressed relative to the cIS. Thus, the WHO has established 11468/16 as the 1st IS for ZIKV RNA, with a unitage of 50,000,000 IU/mL.
Authors: Yann Le Duff; Kathleen Gärtner; Eloise J Busby; Annalisa Dalzini; Sivapragashini Danaviah; José Luis Jiménez Fuentes; Carlo Giaquinto; Jim F Huggett; Matthew Hurley; Anne-Geneviève Marcellin; María Ángeles Muñoz-Fernández; Denise M O'Sullivan; Deborah Persaud; Laura Powell; Peter Rigsby; Paolo Rossi; Anita de Rossi; Lilly Siems; Theresa Smit; Sarah A Watters; Neil Almond; Eleni Nastouli Journal: Microbiol Spectr Date: 2022-06-06
Authors: S A Baylis; E McCulloch; P Wallace; O Donoso Mantke; M Niedrig; J Blümel; C Yue; C M Nübling Journal: J Clin Microbiol Date: 2018-02-22 Impact factor: 5.948
Authors: Carlo Fischer; Celia Pedroso; Alfredo Mendrone; Ana Maria Bispo de Filippis; Antonio Carlos Rosário Vallinoto; Bergmann Morais Ribeiro; Edison Luiz Durigon; Ernesto T A Marques; Gubio S Campos; Isabelle F T Viana; José Eduardo Levi; Luciano Cesar Scarpelli; Mauricio Lacerda Nogueira; Michele de Souza Bastos; Nathalia C Santiago Souza; Ricardo Khouri; Sanny Lira; Shirley Vasconcelos Komninakis; Cécile Baronti; Rémi N Charrel; Beate M Kümmerer; Christian Drosten; Carlos Brites; Xavier de Lamballerie; Matthias Niedrig; Eduardo Martins Netto; Jan Felix Drexler Journal: Emerg Infect Dis Date: 2018-05-17 Impact factor: 6.883