Introduction: Patients being on immunosuppressive treatment of any reason, along with other risk factors such as smoking and obesity, are vulnerable to be infected from SARS-CoV2. Aim of this report is to describe a case of a female patient under Rituximab therapy who experienced episodes of lung infection due to Severe Acute Coronavirus 2 (SARS-CoV-2 ) invasion although fully vaccinated. Case report: A 50-year-old woman, with a past medical history of lupus nephritis on rituximab was diagnosed with lung infection due to SARS-CoV-2. Eight months later, following her last infusion of Rituximab (RTX), she developed moderate Coronavirus Disease 2019 (COVID-19). After a partial recovery, she exhibited exacerbation of respiratory symptoms leading to readmission and invasive oxygenation. She was eventually discharged home after 31 days. Her monthly neurological evaluation did not reveal evidence of disease activity. She later received intravenous immunoglobulin and a decision was made to restart rituximab. Conclusions: This case raises the possibility of persistent virus shedding and reactivation of severe acute respiratory syndrome coronavirus in a patient with SLE and Rituximab therapy. We emphasize a precise consideration of management of patients with autoimmune disorders during the COVID-19 pandemic.