As already well described, BCG vaccination should be avoided not only in SCID, MSMD, and CGD patients (321) but also in other particular newly described PIDD (e.g., STAT1 GOF, APDS1, and APDS2) in which its complication rates have shown to markedly exceed when compared to the general population. The gene discussed is STAT1; the disease is chronic granulomatous disease.