Immunodeficient patients with persistent SARS-CoV-2 infection several months after initial infection may harbour potential for onward transmission of replication-competent virus. Adjunctive viral cell culture supports treatment decision-making in patients with secondary humoral immunodeficiency and persistent SARS-CoV-2 infection Keywords: COVID-19; SARS-CoV-2; recurrence; lymphoma; immune reconstitution EN COVID-19 SARS-CoV-2 recurrence lymphoma immune reconstitution 1170 1174 5 02/28/22 20220301 NES 220301 Persistent Severe Acute Respiratory Syndrome coronavirus-2 (SARS-CoV-2) infection is observed among patients with haematological malignancy, conferring an increased mortality risk.1,2 Persistent SARS-CoV-2 RNA detection from clinical samples may represent redundant fragmented RNA, replication-competent virus, or reinfection.3,4 Given the role of the host immune response in viral clearance and COVID-19 immunopathogenesis,5,6 distinguishing these scenarios is important for therapeutic decision-making (antiviral I versus i immunomodulatory) as well as preventing onward hospital transmission. Investigation The patient was investigated for persisting SARS-CoV-2 infection/reinfection following relapsing symptomatic pneumonitis associated with positive RNA-polymerase chain reaction (PCR) testing after second-round chemotherapy. [Extracted from the article]