State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
Department of Microbiology, Queen Mary Hospital, Hong Kong SAR, China.
Viruses. 2022 Aug 4;14(8):1714. doi: 10.3390/v14081714.
Formulating termination of isolation (de-isolation) policies requires up-to-date knowledge about viral shedding dynamics. However, current de-isolation policies are largely based on viral load data obtained before the emergence of Omicron variant. In this retrospective cohort study involving adult patients hospitalised for COVID-19 between January and February 2022, we sought to determine SARS-CoV-2 viral shedding kinetics and to investigate the risk factors associated with slow viral decline during the 2022 Omicron wave. A total of 104 patients were included. The viral load was highest (Ct value was lowest) on days 1 post-symptom-onset (PSO) and gradually declined. Older age, hypertension, hyperlipidaemia and chronic kidney disease were associated with slow viral decline in the univariate analysis on both day 7 and day 10 PSO, while incomplete or no vaccination was associated with slow viral decline on day 7 PSO only. However, older age was the only risk factor that remained statistically significant in the multivariate analysis. In conclusion, older age is an independent risk factor associated with slow viral decline in this study conducted during the Omicron-dominant 2022 COVID-19 wave. Transmission-based precaution guidelines should take age into consideration when determining the timing of de-isolation.
制定解除隔离（去隔离）政策需要掌握有关病毒脱落动力学的最新知识。然而，目前的去隔离政策在很大程度上是基于奥密克戎变异出现之前获得的病毒载量数据。在这项涉及 2022 年 1 月至 2 月期间因 COVID-19 住院的成年患者的回顾性队列研究中，我们旨在确定 SARS-CoV-2 病毒脱落动力学，并调查与 2022 年奥密克戎浪潮期间病毒下降缓慢相关的危险因素。共纳入 104 例患者。病毒载量在症状出现后第 1 天（PSO）最高（Ct 值最低），并逐渐下降。在 PSO 第 7 天和第 10 天的单变量分析中，年龄较大、高血压、高脂血症和慢性肾脏病与病毒下降缓慢有关，而不完全或未接种疫苗与 PSO 第 7 天的病毒下降缓慢有关。然而，在多变量分析中，只有年龄较大是唯一具有统计学意义的危险因素。总之，在这项针对 2022 年奥密克戎主导的 COVID-19 浪潮期间进行的研究中，年龄较大是与病毒下降缓慢相关的独立危险因素。基于传播的预防指南在确定去隔离时机时应考虑年龄因素。
