부산대학교 도서관

Background: Early detection of human yellow fever (YF) infection in YF-endemic regions is critical to timely outbreak mitigation. African National Laboratories chiefly rely on serological assays that require confirmation at Regional Reference Laboratories, thus delaying results, which themselves are not always definitive often due to antibody cross-reactivity. A positive molecular test result is confirmatory for YF; therefore, a standardized YF molecular assay would facilitate immediate confirmation at National Laboratories. The WHO-coordinated global Eliminate Yellow Fever Epidemics Laboratory Technical Working Group sought to independently evaluate the quality and performance of commercial YF molecular assays relevant to use in countries with endemic YF, in the absence of stringent premarket assessments. This report details a limited laboratory WHO-coordinated evaluation of the altona Diagnostics RealStar Yellow Fever Virus RT-PCR kit 1.0. Methodology and principal findings: Specific objectives were to assess the assay's ability to detect YF virus strains in human serum from YF-endemic regions, determine the potential for interference and cross-reactions, verify the performance claims as stated by the manufacturer, and assess usability. RNA extracted from normal human serum spiked with YF virus showed the assay to be precise with minimal lot-to-lot variation. The 95% limit of detection calculated was approximately 1,245 RNA copies/ml [95% confidence interval 497 to 1,640 copies/ml]. Positive results were obtained with spatially and temporally diverse YF strains. The assay was specific for YF virus, was not subject to endogenous or exogenous interferents, and was clinically sensitive and specific. A review of operational characteristics revealed that a positivity cutoff was not defined in the instructions for use, but otherwise the assay was user-friendly. Conclusions and significance: The RealStar Yellow Fever Virus RT-PCR kit 1.0 has performance characteristics consistent with the manufacturer's claims and is suitable for use in YF-endemic regions. Its use is expected to decrease YF outbreak detection times and be instrumental in saving lives. Author summary: Molecular diagnosis of human specimens is the fastest way to confirm and subsequently mitigate yellow fever (YF) outbreaks. In Africa, a serological method requiring lengthy confirmation external to the National Laboratories is standard and results are not always definitive due to factors such as cross-reactive antibodies. Molecular testing has been uncommon in African YF laboratories, largely due to challenges with acquiring reagents and a lack of an approved assay that simplifies laboratory procedures. In our capacities as members of the global Eliminate Yellow Fever Epidemics strategy, we independently evaluated the RealStar Yellow Fever RT-PCR kit 1.0 (altona Diagnostics, Hamburg, Germany). We showed that the assay is sensitive and specific for detection of RNA from representative YF virus strains found worldwide. It is not subject to interference from common blood contaminants and has good clinical performance. In conjunction with a separately conducted review of the manufacturer's quality systems, we concluded that the RealStar Yellow Fever Virus RT-PCR kit 1.0 is appropriate for use in YF endemic regions. Logistical and funding support to introduce the assay is being arranged, which should decrease YF outbreak detection times and ultimately save lives. [ABSTRACT FROM AUTHOR]