Importance: The global COVID-19 pandemic does not appear to end in the near future. Currently, limited data are available on the risk factors for delayed viral clearance in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection. Objective: This study aimed to investigate the association of clinical characteristics and vaccination with prolonged viral clearance. Methods: This retrospective cohort included 16,985 patients who had contracted the SARS-CoV-2 Omicron variant between April 5 and May 30, 2022, in Shanghai, China, and had mild or no symptoms. The patients were admitted to the quarantine venue at the Shanghai New International Expo Center. Results: Of the 16,985 participants, the occurrence of viral clearance was ≤8 and > 8 days in 11,009 (64.8 %) and 5976 (35.2 %) participants, respectively. Risk factors related to patients who remained persistently polymerase chain reaction (PCR)-positive were sex (Male, odds ratio [OR] 1.221, p < 0.001), older age (35–49, OR 1.389, p < 0.001; 50–64, OR 1.659, p < 0.001; ≥65, OR 2.139, p < 0.001), presence of symptoms (OR 1.093, p = 0.030), number of vaccinations (two doses, OR 0.753, p < 0.001; three doses, OR 0.797, p < 0.001; four doses, OR 0.543, p < 0.001), and cycle threshold (Ct) value for ORF1ab gene at diagnosis (25–35, OR 0.235, p < 0.001; >35, OR 0.079, p < 0.001). The lower rates of increase in Ct values were observed in the later viral shedding group than in the early viral shedding group for ORF1ab (β = −0.791, p < 0.001) and N genes (β = −0.825, p < 0.001). Conclusion: Prolonged SARS-CoV-2 RNA detection and higher viral concentrations were associated with factors such as male sex, older age, symptomatic status, and fewer doses of vaccination in patients admitted to Shanghai Makeshift Hospital between April 5 and May 30, 2022.

ObjectiveTo evaluate determinants of prolonged viral RNA shedding in hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection.Materials and methodsHospitalized patients tested SARS-CoV-2 positive by nasopharyngeal real-time reverse transcriptase-polymerase chain reaction (RT-PCR) were included in the single-center, retrospective study. Patients were divided into 2 groups according to the timing of viral clearance (≤ 8 days, “early clearance” and ≥15 days, “late clearance”).Results4,084 patients were included in the study (1,023 late clearance, 3,061 early clearance), with median age of 50 years and a higher proportion (61.4%) of male. Univariate analyses showed that comorbidities (including hypertension, diabetes, and coronary heart disease), receiving vaccine, the number of vaccinations, cycle threshold (Ct) open reading frame 1ab (ORF 1ab), and nucleocapsid protein (N) gene values on admission were associated with late viral clearance. In the multivariable analysis, the number of vaccinations (P = 0.010) and Ct ORF 1ab gene (P < 0.001) values on admission were significantly associated with late viral clearance. Generalized Estimating Equations (GEE) analysis showed that the Ct value of ORF 1ab gene and N gene remained unchanged within 3 days, and showed progressively higher values with increasing days during late viral RNA clearance.ConclusionThe number of vaccinations and Ct values of ORF 1ab gene were independently associated with a prolonged SARS-CoV-2 RNA shedding.

Guizhi Fuling Formula was first seen in Synopsis of Golden Chamber by ZHANG Zhongjing. It is composed of Cinnamomi Ramulus, Poria, Moutan Cortex, Persicae Semen, Peony and other drugs, commonly used in the treatment of gynecological diseases such as hysteromyoma, ovarian cyst, endometriosis, pelvic inflammation, dysmenorrhea, etc. In addition, it is also used in internal medicine and urology. This reflects the modern doctors' recognition of the famous prescriptions in ancient books. However, whether Guizhi Fuling Formula is really suitable for these diseases still needs further study for verification. The author systematically searched CNKI, Wanfang, SinoMed, PubMed, EMbase, Cochrane Library database: 2 304 papers on clinical research of Guizhi Fuling, covering 13 systems and 128 diseases. Combined with the questionnaire of experts, we investigated the knowledge of experts of traditional Chinese medicine, Western medicine and combination of Chinese and Western medicine on the applicable indications of Guizhi Fuling Formula in this paper, systematically elaborated the clinical applications of Guizhi Fuling Formula, and summarized the applicable indications of Guizhi Fuling Formula, in order to provide a reference for the clinical rational application of Guizhi Fuling Formula, and provide a reference also for clinical medication.