Villarreal Alcibiades, Rangel Giselle, Zhang Xu, Wong Digna, Britton Gabrielle, Fernandez Patricia L, Pérez Ambar, Oviedo Diana, Restrepo Carlos, Carreirra María B, Sambrano Dilcia, Eskildsen Gilberto A, De La Guardia Carolina, Flores-Cuadra Julio, Carrera Jean-Paul, Zaldivar Yamitzel, Franco Danilo, López-Vergès Sandra, Zhang Dexi, Fan Fangjing, Wang Baojun, Sáez-Llorens Xavier, DeAntonio Rodrigo, Torres-Atencio Ivonne, Blanco Isabel, Subía Fernando Diaz, Mudarra Laiss, Benzadon Aron, Valverde Walter, López Lineth, Hurtado Nicolás, Rivas Neyla, Jurado Julio, Carvallo Aixa, Rodriguez Juan, Perez Yaseikiry, Morris Johanna, Luque Odemaris, Cortez David, Ortega-Barria Eduardo, Kosagisharaf Rao, Lleonart Ricardo, Li Chong, Goodridge Amador
Centro de Biología Celular y Molecular de las Enfermedades, City of Knowledge, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), Panama City, Panama.
Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
Front Med (Lausanne). 2021 Mar 2;8:616106. doi: 10.3389/fmed.2021.616106. eCollection 2021.
Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has reached 28 million cases worldwide in 1 year. The serological detection of antibodies against the virus will play a pivotal role in complementing molecular tests to improve diagnostic accuracy, contact tracing, vaccine efficacy testing, and seroprevalence surveillance. Here, we aimed first to evaluate a lateral flow assay's ability to identify specific IgM and IgG antibodies against SARS-CoV-2 and second, to report the seroprevalence estimates of these antibodies among health care workers and healthy volunteer blood donors in Panama. We recruited study participants between April 30th and July 7th, 2020. For the test validation and performance evaluation, we analyzed serum samples from participants with clinical symptoms and confirmed positive RT-PCR for SARS-CoV-2, and a set of pre-pandemic serum samples. We used two by two table analysis to determine the test positive and negative percentage agreement as well as the Kappa agreement value with a 95% confidence interval. Then, we used the lateral flow assay to determine seroprevalence among serum samples from COVID-19 patients, potentially exposed health care workers, and healthy volunteer donors. Our results show this assay reached a positive percent agreement of 97.2% (95% CI 84.2-100.0%) for detecting both IgM and IgG. The assay showed a Kappa of 0.898 (95%CI 0.811-0.985) and 0.918 (95% CI 0.839-0.997) for IgM and IgG, respectively. The evaluation of serum samples from hospitalized COVID-19 patients indicates a correlation between test sensitivity and the number of days since symptom onset; the highest positive percent agreement [87% (95% CI 67.0-96.3%)] was observed at ≥15 days post-symptom onset (PSO). We found an overall antibody seroprevalence of 11.6% (95% CI 8.5-15.8%) among both health care workers and healthy blood donors. Our findings suggest this lateral flow assay could contribute significantly to implementing seroprevalence testing in locations with active community transmission of SARS-CoV-2.
新型严重急性呼吸综合征冠状病毒2（SARS-CoV-2）是正在流行的2019冠状病毒病（COVID-19）大流行的病原体，该病在1年内全球确诊病例已达2800万例。针对该病毒的抗体血清学检测在补充分子检测以提高诊断准确性、接触者追踪、疫苗效力测试和血清流行率监测方面将发挥关键作用。在此，我们的目标一是评估一种侧向流动分析法识别针对SARS-CoV-2的特异性IgM和IgG抗体的能力，二是报告巴拿马医护人员和健康志愿者献血者中这些抗体的血清流行率估计值。我们在2020年4月30日至7月7日期间招募了研究参与者。为了进行测试验证和性能评估，我们分析了有临床症状且经逆转录聚合酶链反应（RT-PCR）确诊为SARS-CoV-2阳性的参与者的血清样本，以及一组疫情前的血清样本。我们使用二乘二表分析法来确定测试的阳性和阴性百分比一致性以及95%置信区间的Kappa一致性值。然后，我们使用侧向流动分析法来确定COVID-19患者、可能接触过病毒的医护人员以及健康志愿者献血者的血清样本中的血清流行率。我们的结果表明，该分析法检测IgM和IgG的阳性百分比一致性达到97.2%（95%置信区间84.2 - 100.0%）。该分析法检测IgM和IgG的Kappa值分别为0.898（95%置信区间0.811 - 0.985）和0.918（95%置信区间839 - 0.997）。对住院COVID-19患者血清样本的评估表明，测试敏感性与症状出现后的天数之间存在相关性；在症状出现后≥15天观察到最高的阳性百分比一致性[87%（95%置信区间67.0 - 96.3%）]。我们发现医护人员和健康献血者中的总体抗体血清流行率为11.6%（95%置信区间8.5 - 15.8%）。我们的研究结果表明，这种侧向流动分析法可对在SARS-CoV-2社区传播活跃的地区开展血清流行率检测做出重大贡献。
