RESUMO
Background: Data on viral kinetics and variants affecting the duration of viral shedding were limited. Our objective was to determine viral shedding in distinct severe acute respiratory syndrome coronavirus 2 variants, including Omicron BA.4/5 and BF.7, and to identify the relevant influencing factors. Methods: We carried out a longitudinal cohort study at Beijing Xiaotangshan Fangcang shelter hospital from May to June 2022 (Omicron BA.4/5) and from November to December 2022 (Omicron BF.7). Nucleocapsid protein (N) and open reading frame (ORF) genes were considered as the target genes of the reverse transcription PCR. The daily results of cycle threshold (CT), including lowest ORF1ab-CT values for days 1-3 post-hospitalisation and lowest N-CT values for days 1-3 post-hospitalisation (CT3minN) and demographic and clinical characteristics were collected. Results: 1433 patients with coronavirus disease 2019 (COVID-19) were recruited from the Fangcang shelter hospital, in which 278 patients were diagnosed with Omicron BA.4/5 and 1155 patients with Omicron BF.7. Patients with BF.7 infection showed a longer duration of viral shedding. The duration of viral shedding was associated with the variants age, alcohol use, the severity of COVID-19 and CT3minN. Moreover, the nomogram had excellent accuracy in predicting viral shedding. Conclusions: Our results indicated that patients with Omicron BF.7 had a longer period of contagiousness than those with BA.4/5. The duration of viral shedding was affected by a variety of factors and the nomogram may become an applicable clinical instrument to predict viral shedding. Furthermore, we developed a new COVID-19 viral shedding predicting model that can accurately predict the duration of viral shedding for COVID-19, and created a user-friendly website to apply this prediction model (https://puh3.shinyapps.io/CVSP_Model/).
RESUMO
Background: Lianhuaqingwen (LHQW), a traditional Chinese medicine comprised of 13 herbal extracts renowned for their robust heat-clearing and detoxifying properties, has gained widespread utilization in China but has yet to garner similar recognition abroad. It is believed to exhibit efficacy in ameliorating symptoms in individuals afflicted with coronavirus disease 2019 (COVID-19). However, the precise impact of LHQW on viral shedding (VS), particularly in the context of mild or asymptomatic infections caused by the Omicron BF.4/5 or BF.7 variants of COVID-19, remained inadequately elucidated. Consequently, a real-world study was conducted, involving patients diagnosed with COVID-19, with the primary objective of ascertaining the effectiveness of LHQW in this specific clinical context. Methods: We conducted an investigation on Omicron-infected patients through a single-center, propensity score-matched real-world study conducted at Xiaotangshan Fangcang Hospital from May to November 2022. A total of 3,368 COVID-19 patients were enrolled in the study, all of whom presented mild or asymptomatic infections caused by either BF.4/5 or BF.7 strains of the virus. Demographic and clinical data were systematically collected from medical records. Patients were allocated to receive treatment with LHQW (designated as the treatment group) or received no LHQW treatment (designated as the not-treated/no-treatment group). Viral load was quantified utilizing quantitative real-time PCR (qPCR), and the duration of VS was defined as the time interval between the initial negative test result and the date of COVID-19 diagnosis or symptom onset. Results: The study encompassed a cohort of 3,368 patients, and following propensity score matching, a subset of 296 patients was meticulously chosen for subsequent analysis. Notably, baseline characteristics exhibited disparities between the treatment and not-treated/no-treatment groups. However, post-matching, these characteristics achieved a commendable level of comparability. Our findings unequivocally demonstrated that there existed no statistically significant disparity in VS. This holds true when comparing patients subjected to LHQW treatment against those not administered LHQW, as well as when contrasting individuals presenting asymptomatic and mild COVID-19 manifestations. Conclusion: No statistically significant difference in VS was observed between patients who underwent LHQW treatment and those who did not. Additional investigations are imperative to provide a comprehensive assessment of LHQW's efficacy, particularly in patients afflicted with severe COVID-19 or those infected with viral strains distinct from BF.4/5 or BF.7.