Centre of Defence Pathology, Royal Centre for Defence Medicine, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham, B15 2WB, UK.
Clinical Infection Department, Chelsea and Westminster NHS Foundation Trust, 369 Fulham Road, London, SW10 9NH, UK.
Sci Rep. 2021 Mar 12;11(1):5860. doi: 10.1038/s41598-021-85247-w.
Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. Case identification is currently made by real-time polymerase chain reaction (PCR) during the acute phase and largely restricted to healthcare laboratories. Serological assays are emerging but independent validation is urgently required to assess their utility. We evaluated five different point-of-care (POC) SARS-CoV-2 antibody test kits against PCR, finding concordance across the assays (n = 15). We subsequently tested 200 patients using the OrientGene COVID-19 IgG/IgM Rapid Test Cassette and find a sensitivity of 74% in the early infection period (day 5-9 post symptom onset), with 100% sensitivity not seen until day 13, demonstrating inferiority to PCR testing in the infectious period. Negative rate was 96%, but in validating the serological tests uncovered potential false-negatives from PCR testing late-presenting cases. A positive predictive value (PPV) of 37% in the general population precludes any use for general screening. Where a case definition is applied however, the PPV is substantially improved (95.4%), supporting use of serology testing in carefully targeted, high-risk populations. Larger studies in specific patient cohorts, including those with mild infection are urgently required to inform on the applicability of POC serological assays to help control the spread of SARS-CoV-2 and improve case finding of patients that may experience late complications.
严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 已成为全球性大流行。目前在急性阶段通过实时聚合酶链反应 (PCR) 进行病例识别，并且主要限于医疗保健实验室。血清学检测正在出现，但迫切需要独立验证来评估其效用。我们评估了五种不同的即时护理 (POC) SARS-CoV-2 抗体检测试剂盒与 PCR 的一致性，发现这些检测之间具有一致性 (n=15)。随后，我们使用 OrientGene COVID-19 IgG/IgM 快速检测试剂盒对 200 名患者进行了测试，发现早期感染期 (症状出现后第 5-9 天) 的敏感性为 74%，直到第 13 天才达到 100%的敏感性，这表明在感染期的敏感性低于 PCR 检测。阴性率为 96%，但在验证血清学检测时，发现了 PCR 检测中潜在的迟发病例假阴性。在普通人群中，阳性预测值 (PPV) 为 37%，因此不适合用于一般筛查。然而，在应用病例定义的情况下，PPV 大大提高 (95.4%)，支持在精心选择的高危人群中使用血清学检测。迫切需要在特定患者群体(包括轻度感染患者)中进行更大规模的研究，以了解 POCT 血清学检测对控制 SARS-CoV-2 传播和发现可能出现迟发并发症的患者的适用性。
