While induction treatment with rituximab, for example in ANCA-associated vasculitis, usually cannot be delayed, postponing COVID-19 vaccination until the reconstitution of CD19+ B-cells, a transient switch to other immunosuppressive treatments (such as azathioprine) or a delay of rituximab treatment in stable patients may be warranted [42]. Here, CD19 is linked to anti-neutrophil cytoplasmic antibody-associated vasculitis.