Liossi Sofia, Tsiambas Evangelos, Maipas Sotirios, Argyropoulou Marilena, Papageorgiou Effie G, Lazaris Andreas C, Kavantzas Nikolaos
First Department of Pathology, School of Medicine, National and Kapodistrian University of Athens, Athens, GRC.
Department of Cytopathology, 417 Army Equity Fund Hospital (NIMTS), Athens, GRC.
Cureus. 2025 Apr 24;17(4):e82955. doi: 10.7759/cureus.82955. eCollection 2025 Apr.
Polymerase chain reaction (PCR) tests are the gold standard for confirming COVID-19. Test results provide the cycle threshold (Ct) value, which is correlated to the patient's viral load as well as hematological and biochemical parameters. The purpose of this study is to analyze the transmission dynamics of selected SARS-CoV-2 variants, both within hosts and between hosts, through statistics and data analysis of the Ct values and other metrics. Demographics data and Ct values from 1,041 patients with COVID-19 were collected and correlated with epidemiological indices, such as the positivity rate, hospitalizations, and deaths for each major wave of the pandemic, in Greece. The analysis showed that higher viral loads coincide with rising pandemic waves, while lower loads are observed during periods of decline. Notably, among all variants analyzed, the Delta variant, observed in mid-2021, exhibited the highest viral load values, which were associated with increased hospitalizations and mortality, despite a relatively low positivity rate. Consequently, variables associated with inter-host transmission dynamics show a significant correlation with those pertaining to intra-host dynamics. This correlation opens up the potential for predicting disease severity and forecasting the trajectory of the pandemic based on patient-related and other variables through data analysis. The analysis revealed that variations in Ct value yield valuable insights into the evolution of the pandemic and the risk stratification of patients. The study highlights that statistical measures derived from Ct values can provide insights into both intra-host and inter-host transmission dynamics, potentially supporting risk assessment and public health responses.
聚合酶链反应（PCR）检测是确诊新冠病毒的金标准。检测结果会提供循环阈值（Ct）值，该值与患者的病毒载量以及血液学和生化参数相关。本研究的目的是通过对Ct值和其他指标进行统计和数据分析，来分析特定新冠病毒变异株在宿主内和宿主间的传播动态。收集了希腊1041例新冠患者的人口统计学数据和Ct值，并将其与流行病学指标相关联，如疫情各主要波次的阳性率、住院率和死亡率。分析表明，较高的病毒载量与疫情波次上升同时出现，而在疫情下降期间观察到较低的病毒载量。值得注意的是，在所有分析的变异株中，2021年年中出现的德尔塔变异株表现出最高的病毒载量值，尽管其阳性率相对较低，但却与住院率和死亡率的增加相关。因此，与宿主间传播动态相关的变量与宿主内动态相关的变量显示出显著的相关性。这种相关性为通过数据分析，基于患者相关及其他变量预测疾病严重程度和疫情发展轨迹开辟了潜力。分析显示，Ct值的变化为疫情演变和患者风险分层提供了有价值的见解。该研究强调，从Ct值得出的统计指标可以为宿主内和宿主间的传播动态提供见解，可能有助于风险评估和公共卫生应对措施。
