STAT1 and Alzheimer disease: Intracellular bacterial infections caused by disseminated Mycobacterium bovis Bacillus Calmette–Guérin (BCG) vaccine, nontuberculosis mycobacteria, e.g., Mycobacterium avium, frequently manifesting as multifocal osteomyelitis, are commonly observed in patients with AD STAT1 deficiency (1).