Isolation of SARS-CoV-2 in Viral Cell Culture in Immunocompromised Patients With Persistently Positive RT-PCR Results

Abstract

Immunocompromised adults can have prolonged acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive RT-PCR results, long after the initial diagnosis of coronavirus disease 2019 (COVID-19). This study aimed to determine if SARS-CoV-2 virus can be recovered in viral cell culture from immunocompromised adults with persistently positive SARS-CoV-2 RT-PCR tests. We obtained 20 remnant SARS-CoV-2 PCR positive nasopharyngeal swabs from 20 immunocompromised adults with a positive RT-PCR test ≥14 days after the initial positive test. The patients’ 2nd test samples underwent SARS-CoV-2 antigen testing, and culture with Vero-hACE2-TMPRSS2 cells. Viral RNA and cultivable virus were recovered from the cultured cells after qRT-PCR and plaque assays. Of 20 patients, 10 (50%) had a solid organ transplant and 5 (25%) had a hematologic malignancy. For most patients, RT-PCR Ct values increased over time. There were 2 patients with positive viral cell cultures; one patient had chronic lymphocytic leukemia treated with venetoclax and obinutuzumab who had a low viral titer of 27 PFU/mL. The second patient had marginal zone lymphoma treated with bendamustine and rituximab who had a high viral titer of 2 x 106 PFU/mL. Most samples collected ≥7 days after an initial positive SARS-CoV-2 RT-PCR had negative viral cell cultures. The 2 patients with positive viral cell cultures had hematologic malignancies treated with chemotherapy and B cell depleting therapy. One patient had a high concentration titer of cultivable virus. Further data are needed to determine risk factors for persistent viral shedding and methods to prevent SARS-CoV-2 transmission from immunocompromised hosts.

Successful Elimination of SARS-CoV-2 Following Vaccination with BNT162b2 after Prolonged Viral Infection in an Immunocompromised Lymphoma Patient

“…We then speculated that either the virus in the present case had lost aggressiveness or the acquired anti-SARS-CoV-2 antibodies had restrained proliferation in the respiratory airways. Recently, several cases of COVID-19 after bendamustine and rituximab-treatment have been reported (25)(26)(27)(28). In these reports, even with prolonged viral shedding, the clinical outcomes were not always unfavorable.…”

Nanomaterials to combat SARS-CoV-2: Strategies to prevent, diagnose and treat COVID-19

“…The sequencing of bronchoalveolar lavage fluid samples of the above nine patients again identified the new CoV (Barton et al, 2020). More evidence for the presence of this CoV was obtained by virus isolation form the clinical specimens, viral culture, and cytotoxicity assays together with virus morphology analysis by electron microscopy (Barton et al, 2020;Cao et al, 2020), all of which are methods and devices that clearly use key nanotechnologies for SARS-CoV-2/COVID-19 detection and diagnosis (Caldas et al, 2020;Prasad et al, 2020;Akilesh et al, 2021;Jefferson et al, 2021;Sung et al, 2022).…”

SARS-CoV-2 coinfections with variant genomic lineages identified by multiplex fragment analysis

“…Host immunity (natural or vaccine-derived) also drives the emergence of strains with advantageous mutations (Di Caro et al, 2021). We and others have observed immunocompromised (IC) hosts can exhibit persistently positive SARS-CoV-2 RT-PCR tests long after initial COVID-19 diagnosis, with replication-competent virus recovered in some cases (Sung et al, 2022). Moreover, IC patients often fail to mount robust immunological responses to vaccination (Narasimhan et al, 2021;Thakkar et al, 2021;Vijenthira et al, 2021) and are more susceptible to breakthrough infections (Sun et al, 2022).…”