Immunodeficiency or immunosuppression are characterized by the absence of or disruption in components of the immune system, leading to lower-than-normal levels of immune function and immunity against pathogens. They can be caused by a variety of factors, including: * Malnutrition * Fatigue * Recurrent infections * Immunosuppressing agents for organ transplant recipients * Advanced HIV infection * Chemotherapy for cancer * Genetic predisposition * Skin damage * Antibiotic treatment leading to disruption of the physiological microbiome, thus allowing some microorganisms to outcompete others and become pathogenic (e.g. disruption of intestinal microbiota may lead to Clostridium difficile infection) * Medical procedures * Pregnancy * Aging * Leukopenia (i.e. neutropenia and lymphocytopenia) * Burns The lack of or the disruption of normal vaginal microbiota allows the proliferation of<unk>  microorganisms and will cause the<unk>  bacterial vaginosis.
Opportunistic infection
Spillover infection
Intentional contagion of infection
Blood-borne disease
Viral pathogenesis
Superinfection
Breakthrough infection
Laboratory-acquired infection