Analysis of circulating B cell populations using flow cytometry revealed that, following SARS-CoV-2 infection, both groups of COVID-19 patients (with and without ARDS) showed a significantly higher percentage of total B cells (CD19+CD20+) and plasmablasts (CD19+CD20+CD27CD24-CD38hi) compared to healthy controls. The gene discussed is CD19; the disease is COVID-19.