These authors contributed equally to this article and share the first authorship.
Department of Information and Knowledge Engineering, Faculty of Informatics and Statistics, Prague University of Economics and Business, Prague, Czechia.
Euro Surveill. 2023 Sep;28(38). doi: 10.2807/1560-7917.ES.2023.28.38.2200938.
BackgroundThe sensitivity and specificity of selected antigen detection rapid diagnostic tests (AG-RDTs) for SARS-CoV-2 were determined in the unvaccinated population when the Delta variant was circulating. Viral loads, dynamics, symptoms and tissue tropism differ between Omicron and Delta.AimWe aimed to compare AG-RDT sensitivity and specificity in selected subgroups during Omicron vs Delta circulation.MethodsWe retrospectively paired AG-RDT results with PCRs registered in Czechia's Information System for Infectious Diseases from 1 to 25 December 2021 (Delta, n = 20,121) and 20 January to 24 February 2022 (Omicron, n = 47,104).ResultsWhen confirmatory PCR was conducted on the same day as AG-RDT as a proxy for antigen testing close to peak viral load, the average sensitivity for Delta was 80.4% and for Omicron 81.4% (p < 0.05). Sensitivity in vaccinated individuals was lower for Omicron (OR = 0.94; 95% confidence interval (CI): 0.87-1.03), particularly in reinfections (OR = 0.83; 95% CI: 0.75-0.92). Saliva AG-RDT sensitivity was below average for both Delta (74.4%) and Omicron (78.4%). Tests on the European Union Category A list had higher sensitivity than tests in Category B. The highest sensitivity for Omicron (88.5%) was recorded for patients with loss of smell or taste, however, these symptoms were almost 10-fold less common than for Delta. The sensitivity of AG-RDTs performed on initially asymptomatic individuals done 1, 2 or 3 days before a positive PCR test was consistently lower for Omicron compared with Delta.ConclusionSensitivity for Omicron was lower in subgroups that may become more common if SARS-CoV-2 becomes an endemic virus.
在德尔塔变异株流行时，我们测定了针对未接种人群中 SARS-CoV-2 的选定抗原检测快速诊断试验（AG-RDT）的敏感性和特异性。奥密克戎与德尔塔变异株的病毒载量、动力学、症状和组织嗜性均有所不同。
我们旨在比较奥密克戎与德尔塔变异株流行期间选定亚组中的 AG-RDT 敏感性和特异性。
我们回顾性地将 AG-RDT 结果与捷克传染病信息系统中 2021 年 12 月 1 日至 25 日（德尔塔，n=20,121）和 2022 年 1 月 20 日至 2 月 24 日（奥密克戎，n=47,104）登记的 PCR 进行配对。
当 AG-RDT 与 PCR 在同一天进行时，作为接近病毒载量峰值的抗原检测的替代方法，德尔塔的平均敏感性为 80.4%，奥密克戎为 81.4%（p<0.05）。奥密克戎的疫苗接种者敏感性较低（OR=0.94；95%置信区间（CI）：0.87-1.03），尤其是在再感染时（OR=0.83；95%CI：0.75-0.92）。唾液 AG-RDT 对德尔塔（74.4%）和奥密克戎（78.4%）的敏感性均低于平均水平。欧盟 A 类清单上的检测比 B 类清单上的检测具有更高的敏感性。奥密克戎的最高敏感性（88.5%）见于嗅觉或味觉丧失的患者，但这些症状比德尔塔少见近 10 倍。与德尔塔相比，奥密克戎在最初无症状的个体中，在 PCR 检测呈阳性前 1、2 或 3 天进行的 AG-RDT 敏感性始终较低。
如果 SARS-CoV-2 成为一种地方性病毒，奥密克戎的敏感性在亚组中可能会更低，这些亚组可能会变得更为常见。
