Probable causes and risk factors for positive SARS‐CoV‐2 test in recovered patients: Evidence from Brunei Darussalam

Wong, Justin; Koh, Wee Chian; Momin, Riamiza Natalie; Alikhan, Mohammad Fathi; Fadillah, Noraskhin; Naing, Lin

Case reports of COVID‐19 patients who have been discharged and subsequently report positive RT‐PCR again (hereafter referred as ‘re‐positive’) do not fully describe the magnitude and significance of this issue. In order to determine the re‐positive rate (proportion) and review probable causes and outcomes, we conduct a retrospective study of all 119 discharged patients in Brunei Darussalam up till April 23. Patients who were discharged are required to self‐isolate at home for 14 days and undergo NP specimen collection post‐discharge. Discharged patients found to be re‐positive were readmitted. We reviewed the clinical and epidemiological records of all discharged patients and apply log‐binomial models to obtain risk ratios for re‐positive status. One in five recovered patients subsequently test positive again for SARS‐CoV‐2 – this risk is more than six times higher in persons aged 60 years and above. The average Ct value of re‐positive patients was lower pre‐discharge compared to their readmission Ct value. Out of 111 close contacts tested, none were found to be positive as a result of exposure to a re‐positive patient. Our findings support prolonged but intermittent viral shedding as the probable cause for this phenomenon. We did not observe infectivity potential in these patients. This article is protected by copyright. All rights reserved.