Virological characteristics and the rapid antigen test as deisolation criteria in immunocompromised patients with COVID-19: A prospective cohort study

J Med Virol. 2023 Nov;95(11):e29228. doi: 10.1002/jmv.29228.


There are limited data supporting current Centers for Disease Control and Prevention guidelines for the isolation period in moderate to severely immunocompromised patients with coronavirus disease 2019 (COVID-19). Adult COVID-19 patients who underwent solid organ transplantation (SOT) or received active chemotherapy against hematologic malignancy were enrolled and weekly respiratory samples were collected. Samples with positive genomic real-time polymerase chain reaction results underwent virus culture and rapid antigen testing (RAT). A total of 65 patients (40 with hematologic malignancy and 25 SOT) were enrolled. The median duration of viable virus shedding was 4 weeks (interquartile range: 3-7). Multivariable analysis revealed that B-cell depletion (hazard ratio [HR]: 4.76) was associated with prolonged viral shedding, and COVID-19 vaccination (≥3 doses) was negatively associated with prolonged viral shedding (HR: 0.22). The sensitivity, specificity, positive predictive value, and negative predictive value of RAT for viable virus shedding were 79%, 76%, 74%, and 81%, respectively. The negative predictive value of RAT was only 48% (95% confidence interval [CI]: 33-65) in the samples from those with symptom onset ≤20 days, but it was as high as 92% (95% CI: 85-96) in the samples from those with symptom onset >20 days. About half of immunocompromised COVID-19 patients shed viable virus for ≥4 weeks from the diagnosis, and virus shedding was prolonged especially in unvaccinated patients with B-cell-depleting therapy treatment. RAT beyond 20 days in immunocompromised patients had a relatively high negative predictive value for viable virus shedding.

Keywords: SARS-CoV-2; infection dynamics; virus shedding.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • COVID-19 Vaccines
  • COVID-19* / diagnosis
  • Hematologic Neoplasms* / complications
  • Humans
  • Prospective Studies
  • RNA, Viral / analysis
  • SARS-CoV-2
  • Virus Shedding


  • COVID-19 Vaccines
  • RNA, Viral