- Individuals With A History Of Splenectomy, Known Immune Disorders (E.G., Systemic Lupus Erythematosus, Rheumatoid Arthritis), Or Receiving Immunosuppressives (E.G., Substances Or Treatments Known To Diminish Immune Response Such As Radiation Therapy, Administration Of Antimetabolites, Antilymphocytic Sera, Systemic Corticosteroids)