The diagnostic utility of Immunoglobulin G (IgG) avidity in distinguishing between past and acute infection of West Nile Virus (WNV).

IF 5.4 2区 医学 Q1 MICROBIOLOGY
Yaniv Lustig, Vicki Indenbaum, Ravit Koren, Shiri Katz-Likvornik, Osnat Halpern, Ella Mendelson
{"title":"The diagnostic utility of Immunoglobulin G (IgG) avidity in distinguishing between past and acute infection of West Nile Virus (WNV).","authors":"Yaniv Lustig, Vicki Indenbaum, Ravit Koren, Shiri Katz-Likvornik, Osnat Halpern, Ella Mendelson","doi":"10.1128/jcm.00952-25","DOIUrl":null,"url":null,"abstract":"<p><p>Infection with West Nile Virus (WNV) can cause severe disease; however, due to immunoglobulin M (IgM) persistence and short viremia, confirmatory diagnosis of acute WNV infection often requires two consecutive samples and a laborious neutralization assay. Immunoglobulin G (IgG) avidity assay is being used to differentiate between acute and past infection of several viral diseases but not of WNV. To test whether IgG avidity can be utilized for WNV diagnosis, serum samples from 103 past and 84 acute WNV-infected persons diagnosed in our laboratory according to WHO guidelines were subjected to IgG avidity. ROC curve analysis was applied to measure the diagnostic accuracy of WNV IgG avidity and establish the optimal cut-off. Mean avidity and geometric mean neutralization titers (GMTs) from acute and past infected cases were 26% (95% CI: 21-30) and 183 (95% CI: 144-235) and 63% (95% CI: 59-67) and 110 (95% CI: 82-147), respectively. Optimal avidity cut-off level to distinguish between acute and past infection was 35% with sensitivity, specificity, PPV, and NPV of 81% (95% CI: 72-88), 88% (95% CI: 81-93), 55% (95% CI: 42-67), and 96% (95% CI: 94-98), respectively. Our results suggest that IgG avidity can rule out acute WNV infections in patients with positive WNV IgM and IgG antibodies and replace the neutralization assay as a confirmatory assay in most cases. By using an avidity assay as part of the routine diagnostic protocol of WNV, the diagnosis of WNV will be simplified, rapid, and would substantially reduce the workload and diagnostic difficulty of this flaviviral infection.IMPORTANCEDiagnosing West Nile Virus (WNV) infection typically requires two serum samples collected weeks apart and a labor-intensive confirmatory test using live virus. Here, we evaluated immunoglobulin G (IgG) avidity assay, which measures the binding strength between WNV antigen and IgG antibodies, as a simpler diagnostic approach using only one sample. Our findings showed that IgG avidity reliably identifies past WNV infections but is less effective in confirming the acute phase. Crucially, this method can rule out acute infections and allow for a rapid and definitive diagnosis in most cases. IgG avidity assays offer a streamlined alternative, reducing the need for complex tests and prolonged timelines.</p>","PeriodicalId":15511,"journal":{"name":"Journal of Clinical Microbiology","volume":" ","pages":"e0095225"},"PeriodicalIF":5.4000,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Clinical Microbiology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1128/jcm.00952-25","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MICROBIOLOGY","Score":null,"Total":0}
引用次数: 0

Abstract

Infection with West Nile Virus (WNV) can cause severe disease; however, due to immunoglobulin M (IgM) persistence and short viremia, confirmatory diagnosis of acute WNV infection often requires two consecutive samples and a laborious neutralization assay. Immunoglobulin G (IgG) avidity assay is being used to differentiate between acute and past infection of several viral diseases but not of WNV. To test whether IgG avidity can be utilized for WNV diagnosis, serum samples from 103 past and 84 acute WNV-infected persons diagnosed in our laboratory according to WHO guidelines were subjected to IgG avidity. ROC curve analysis was applied to measure the diagnostic accuracy of WNV IgG avidity and establish the optimal cut-off. Mean avidity and geometric mean neutralization titers (GMTs) from acute and past infected cases were 26% (95% CI: 21-30) and 183 (95% CI: 144-235) and 63% (95% CI: 59-67) and 110 (95% CI: 82-147), respectively. Optimal avidity cut-off level to distinguish between acute and past infection was 35% with sensitivity, specificity, PPV, and NPV of 81% (95% CI: 72-88), 88% (95% CI: 81-93), 55% (95% CI: 42-67), and 96% (95% CI: 94-98), respectively. Our results suggest that IgG avidity can rule out acute WNV infections in patients with positive WNV IgM and IgG antibodies and replace the neutralization assay as a confirmatory assay in most cases. By using an avidity assay as part of the routine diagnostic protocol of WNV, the diagnosis of WNV will be simplified, rapid, and would substantially reduce the workload and diagnostic difficulty of this flaviviral infection.IMPORTANCEDiagnosing West Nile Virus (WNV) infection typically requires two serum samples collected weeks apart and a labor-intensive confirmatory test using live virus. Here, we evaluated immunoglobulin G (IgG) avidity assay, which measures the binding strength between WNV antigen and IgG antibodies, as a simpler diagnostic approach using only one sample. Our findings showed that IgG avidity reliably identifies past WNV infections but is less effective in confirming the acute phase. Crucially, this method can rule out acute infections and allow for a rapid and definitive diagnosis in most cases. IgG avidity assays offer a streamlined alternative, reducing the need for complex tests and prolonged timelines.

免疫球蛋白G (IgG)在区分过去和急性西尼罗病毒(WNV)感染中的诊断效用。
感染西尼罗病毒(WNV)可导致严重疾病;然而,由于免疫球蛋白M (IgM)的持久性和短期病毒血症,确诊急性西尼罗河病毒感染通常需要连续两次取样和费力的中和试验。免疫球蛋白G (IgG)亲和力测定被用于区分几种病毒性疾病的急性感染和既往感染,但不适用于西尼罗河病毒。为检验IgG抗体检测是否可用于西尼罗河病毒的诊断,本实验室根据WHO指南诊断的103例既往西尼罗河病毒感染者和84例急性西尼罗河病毒感染者进行血清IgG抗体检测。采用ROC曲线分析方法测定WNV IgG抗体的诊断准确率,建立最佳临界值。急性和既往感染病例的平均贪婪度和几何平均中和滴度(GMTs)分别为26% (95% CI: 21-30)和183 (95% CI: 144-235), 63% (95% CI: 59-67)和110 (95% CI: 82-147)。区分急性感染和既往感染的最佳亲和力临界值为35%,敏感性、特异性、PPV和NPV分别为81% (95% CI: 72-88)、88% (95% CI: 81-93)、55% (95% CI: 42-67)和96% (95% CI: 94-98)。我们的研究结果表明,在WNV IgM和IgG抗体阳性的患者中,IgG贪婪度可以排除急性WNV感染,并在大多数情况下取代中和试验作为确认试验。通过将亲和度测定作为西尼罗河病毒常规诊断方案的一部分,西尼罗河病毒的诊断将简化、快速,并将大大减少这种黄病毒感染的工作量和诊断难度。诊断西尼罗病毒(WNV)感染通常需要相隔几周采集两次血清样本,并使用活病毒进行劳力密集的确认试验。在这里,我们评估了免疫球蛋白G (IgG)亲和力测定法,它测量了西尼罗河病毒抗原和IgG抗体之间的结合强度,作为一种仅使用一个样本的更简单的诊断方法。我们的研究结果表明,IgG的亲和力可靠地识别过去的西尼罗河病毒感染,但在确认急性期时效果较差。至关重要的是,这种方法可以排除急性感染,并允许在大多数情况下快速和明确的诊断。IgG亲和度测定提供了一种简化的替代方法,减少了复杂测试的需要和延长的时间。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Journal of Clinical Microbiology
Journal of Clinical Microbiology 医学-微生物学
CiteScore
17.10
自引率
4.30%
发文量
347
审稿时长
3 months
期刊介绍: The Journal of Clinical Microbiology® disseminates the latest research concerning the laboratory diagnosis of human and animal infections, along with the laboratory's role in epidemiology and the management of infectious diseases.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术官方微信