Department of Microbiology, Faculty of Natural and Applied Sciences, Nasarawa State University, Keffi, Nasarawa State, Nigeria.
Primary Health Care Board, Federal Capital Territory Administration, Abuja, Nigeria.
Pan Afr Med J. 2021 May 3;39:3. doi: 10.11604/pamj.2021.39.3.26471. eCollection 2021.
While molecular techniques remain the gold standard for diagnosis of acute SARS-CoV-2 infection, serological tests have the unique potential to ascertain how much of the population has been exposed to the COVID-19 pathogen. There have been limited published studies to date documenting the performance of SARS-CoV-2 antibody assays in Nigeria and so we evaluated the diagnostic performance of five (5) immunoassay on a set of clinical samples. Five automated immunoassays (2019-nCoV IgG/IgM antibody determination kit, Tigsun COVID-19 combo IgM/IgG rapid test, rapid response COVID-19 IgG/IgM test, COVID-19 IgM-IgG combined antibody rapid test, iChroma COVID-19 Ab) were tested. Three hundred and fourteen specimens were analyzed from health care workers who tested positive PCR for SARS-CoV-2 with symptoms consistent with SARS-CoV-2 receiving treatment at two treatment centres in Nasarawa State from March to September, 2020 with control of 134 health care workers who tested negative PCR for SARS-CoV-2 with no symptoms to SARS-CoV-2. The median patients' age was 40 years (IQR 39.8-41), majority were male and were on admission. The SARS-CoV-2 IgG/IgM antibody evaluated kits had a sensitivity of 33% (2019-nCoV IgG/IgM antibody determination kit), 22% (Tigsun COVID-19 combo IgM/IgG rapid test), 43% (rapid response COVID-19 IgG/IgM test), 44% (COVID-19 IgM-IgG combined antibody rapid test), 25% (iChroma COVID-19 Ab), 100% sensitivity, accuracy of 68.5% and Kappa coefficient of 0.7 and rapid response COVID-19 IgG/IgM test cassette had a sensitivity of 33%, specificity of 100% and accuracy of 72.5% with Kappa coefficient 0.7. The Tigsun COVID-19 combo IgM/IgG rapid test (lateral flow), positive, COVID-19 IgM-IgG combined antibody rapid test and iChroma COVID-19 Ab RT all had sensitivity of zero percent. Serology was complementary to RT-PCR for the diagnosis of COVID-19 at least 14 days after onset of symptoms. The assay panel needs to be improved to serve as an option for the diagnosis of SARS-CoV-2 in resource constrained settings where there are limited molecular diagnostics testing panels.
虽然分子技术仍然是诊断急性 SARS-CoV-2 感染的金标准，但血清学检测具有独特的潜力，可以确定有多少人口接触过 COVID-19 病原体。迄今为止，尼日利亚已经发表了有限的研究来记录 SARS-CoV-2 抗体检测的表现，因此我们评估了五（5）种免疫测定在一组临床样本中的诊断性能。测试了五种自动化免疫测定（2019-nCoV IgG/IgM 抗体测定试剂盒、Tigsun COVID-19 组合 IgM/IgG 快速检测试剂盒、快速反应 COVID-19 IgG/IgM 检测试剂盒、COVID-19 IgM-IgG 联合抗体快速检测试剂盒、iChroma COVID-19 Ab）。对 2020 年 3 月至 9 月在纳萨拉瓦州的两个治疗中心接受治疗的症状与 SARS-CoV-2 一致的 SARS-CoV-2 阳性 PCR 检测的医护人员的 314 份样本进行了分析，对照组为 134 名 SARS-CoV-2 阴性 PCR 检测且无 SARS-CoV-2 症状的医护人员。中位患者年龄为 40 岁（IQR 39.8-41），大多数为男性且正在入院。评估的 SARS-CoV-2 IgG/IgM 抗体试剂盒的敏感性分别为 33%（2019-nCoV IgG/IgM 抗体测定试剂盒）、22%（Tigsun COVID-19 组合 IgM/IgG 快速检测试剂盒）、43%（快速反应 COVID-19 IgG/IgM 检测试剂盒）、44%（COVID-19 IgM-IgG 联合抗体快速检测试剂盒）、25%（iChroma COVID-19 Ab）、100%敏感性、68.5%准确性和 0.7 的 Kappa 系数，快速反应 COVID-19 IgG/IgM 测试盒的敏感性为 33%，特异性为 100%，准确性为 72.5%，Kappa 系数为 0.7。Tigsun COVID-19 组合 IgM/IgG 快速检测（侧流）、COVID-19 IgM-IgG 联合抗体快速检测和 iChroma COVID-19 Ab RT 的敏感性均为零。血清学检测至少在症状出现后 14 天与 RT-PCR 互补，用于 COVID-19 的诊断。在资源有限的环境中，由于分子诊断检测面板有限，因此需要改进检测面板，以作为 SARS-CoV-2 诊断的一种选择。
