People are considered to be moderately or severely immunocompromised (have a weakened immune system) due to several types of conditions and treatments. Examples include:
-Been receiving active cancer treatment for tumors or cancers of the blood
-Received an organ transplant and are taking medicine to suppress the immune system
-Received chimeric antigen receptor (CAR)-T-cell therapy (a treatment to help your immune system attach to and kill cancer cells) or received a stem cell transplant (within the last 2 years)
-Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
-Advanced or untreated HIV infection
-Active treatment with high-dose corticosteroids or other drugs that may suppress their immune response