STAT3 and Immunodeficiency: Those at greatest risk of invasive infections are individuals with primary immune deficiencies, such as caspase recruitment domain-containing protein 9 (CARD9) or signal transducer and activator of transcription 3 (STAT3), or acquired immune deficiencies, including those on immunosuppressants such as transplant recipients, those with cancers, and those with HIV/AIDS [5].