Duration of infectious shedding of SARS-CoV-2 Omicron variant and its relation with symptoms

Objectives: SARS-CoV-2 infections with Omicron variants have a high capability of human-to-human transmission. Nevertheless, the duration of isolation for mild cases was shortened to 5 to 7 days. We aimed to detect the duration of viral shedding among healthcare workers (HCWs) with Omicron by using viral culture.Methods: We prospectively included newly diagnosed nonsevere, symptomatic SARS-CoV-2 positive HCWs. Nasopharyngeal swab samples were obtained consecutively on days 5, 7,10, and 14 of onset of symptoms. The samples were examined by nucleic acid amplification test and viral culture.Results: In total, 55 non-severe patients with SARS-CoV-2 Omicron variant were included. The mean age of the population was 34 years (range, 23 to 54) and 78% (43/55) were female. The PCR positivity rate on days 5, 7, 10, and 14 was 96.4% (53/55), 87.3% (48/55), 74.545% (41/55), and 41.8% (23/55) consecutively, whereas the viral culture positivity rates were 83% (44/53), 52% (26/50), 13.5% (7/52), and 8% (4/50). Among the patients who became symptom-free, the viral culture positivity rates were 100% (4/4), 58% (7/ 12), 11% (3/27), and 5% (2/41).Discussion: We showed that among the SARS-CoV-2 Omicron variant infected patients, viral shedding continues for >= 10 days in 13.5% of all cases and 11% in symptom-free cases. The decision for cessation of isolation according to the presence of symptoms could be reconsidered until further studies disapprove of our results. Meanwhile, the infected HCWs who give care to high-risk patients for severe COVID-19 might extend their isolations <= 10 days after the onset of symptoms, regardless of their symptoms. S,iran Keske, Clin Microbiol Infect 2023;29:221 (c) 2022 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study aimed to determine the duration of viral shedding among healthcare workers (HCWs) with Omicron variant by using viral culture. The results showed that viral shedding of Omicron variant infection lasted for at least 10 days in patients, and 11% in symptom-free patients. Therefore, the decision to stop isolation should be reconsidered. Meanwhile, infected HCWs who provide care to high-risk patients for severe COVID-19 may extend their isolation for at least 10 days after the onset of symptoms.