SARS-CoV-2 (severe acute respiratory syndrome coronavirus type 2) is a novel virus that has been identified as a causal agent of COVID-19, an emergent infectious disease which brought about a new pandemic in the twenty-first century. The immune responses and clinical features of individuals infected with SARS-CoV-2 have not yet been fully described. Thus, in this study, we compare the seroprevalence and define the correlation between symptoms and serological results in the first COVID-19 cluster in the city of Konjic, Bosnia and Herzegovina. Of the total number, 93% of RT-PCR positive participants had positive IgG serology and 75% of them developed symptoms of COVID-19. We found that there was no significant alteration in specific IgG (p = 0.504) antibody levels during the 1-year period after COVID-19. Our results indicate that symptomatic COVID-19 patients have a higher rate of seroconversion (p < 0.01). The IgG seroconversion was correlated with high fever (p = 0.002) and headache (p = 0.007), suggesting that these symptoms could be considered as indicators of a better immune response. This study has demonstrated persistence of sustained levels of specific SARS-CoV-2 antibodies after recovering from COVID-19 infection. However, in order to gain a better insight into the immune response to SARS-CoV-2, further systematic studies should be focused on quality and longevity analyses.

中文翻译：

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感染一年后 SARS-CoV-2 抗体的持续血清阳性率：波斯尼亚和黑塞哥维那首批 COVID-19 聚集性病例之一。

SARS-CoV-2（严重急性呼吸综合征冠状病毒 2 型）是一种新型病毒，已被确定为 COVID-19 的病原体，这是一种在 21 世纪引起新流行病的突发传染病。感染 SARS-CoV-2 的个体的免疫反应和临床特征尚未完全描述。因此，在本研究中，我们比较了波斯尼亚和黑塞哥维那 Konjic 市第一个 COVID-19 集群中的血清流行率并确定了症状和血清学结果之间的相关性。在总数中，93% 的 RT-PCR 阳性参与者的 IgG 血清学呈阳性，其中 75% 出现 COVID-19 症状。我们发现，在 COVID-19 之后的 1 年内，特异性 IgG (p = 0.504) 抗体水平没有显着变化。我们的结果表明，有症状的 COVID-19 患者的血清转化率更高（p < 0.01）。IgG 血清转换与高烧 (p = 0.002) 和头痛 (p = 0.007) 相关，表明这些症状可被视为更好免疫反应的指标。这项研究表明，在从 COVID-19 感染中恢复后，特定 SARS-CoV-2 抗体的持续水平持续存在。然而，为了更好地了解对 SARS-CoV-2 的免疫反应，进一步的系统研究应该集中在质量和寿命分析上。这项研究表明，在从 COVID-19 感染中恢复后，特定 SARS-CoV-2 抗体的持续水平持续存在。然而，为了更好地了解对 SARS-CoV-2 的免疫反应，进一步的系统研究应该集中在质量和寿命分析上。这项研究表明，在从 COVID-19 感染中恢复后，特定 SARS-CoV-2 抗体的持续水平持续存在。然而，为了更好地了解对 SARS-CoV-2 的免疫反应，进一步的系统研究应该集中在质量和寿命分析上。