Factors Associated with a prolonged negative conversion of viral RNA in patients with Coronavirus Disease 2019 (COVID-19)

Bennasrallah, Cyrine; Zemni, Imen; Dhouib, Wafa; Sriha, Haythem; Mezhoud, Nourhene; Bouslama, Samar; Taboubi, Wael; Beji, Meriem Oumaima; Kacem, Meriem; Abroug, Hela; Fredj, Manel Ben; Loussaief, Chawki; Belguith, Asma Sriha

Objectives Our study aimed to identify the factors influencing the delay in SARS-CoV-2 RNA negative conversion. Methods A cohort study including COVID-19 patients admitted to the Tunisian national containment center was conducted. The follow-up consisted of a weekly RT-PCR test. Multivariate Cox regression analysis was performed to determine independent predictors associated to negative RNA conversion. Results Among 264 patients included, the median duration of viral clearance was 20 days (IQR (Interquartile Range), 17–32). The shortest and longest durations were nine and 58 days, respectively. Associated factors to negative conversion of viral RNA, were symptoms such as fatigue, fever and shortness of breath (HR (Hazard Ratio): 0.600; 95% CI: 0.401-0.897) and face masks use when exposed to COVID-19 cases (HR: 2.006; 95%CI:1.247-3.228). The median time to RNA viral conversion was 18 days (IQR, 16-21) when using masks vs 23 days (IQR, 17-36) without wearing masks, and 24 days (IQR, 18-36) for symptomatic patients vs 20 days (IQR, 16-30) for asymptomatic ones. Conclusion Our results revealed that during SARS-CoV-2 infection, having symptoms delayed viral clearance, while wearing masks accelerated this conversion. These factors should be harp on consideration for the strategy of isolating infected patients.