Immunodeficiency disorders prevent your body from adequately fighting infections and diseases. An immunodeficiency disorder also makes it easier for you to catch viruses and bacterial infections in the first place. People who have a family history of primary disorders have a higher-than-normal risk for developing primary disorders.
It has been estimated that there are 100 different primary immunodeficiency diseases. All are genetic conditions in which specific cells of the immune system do not function properly. Clinical symptoms range from mild or nonexistent as in the case of selective IgA deficiency to severe symptoms as in the case of severe combined immunodeficiency (SCID), commonly referred to as "bubble-boy" syndrome.
The treatment for each immunodeficiency disorder will be tailored to its specific conditions. For example, AIDS causes several different infections. Your doctor will prescribe medications that are appropriate for each infection. Secondary disorders can be prevented in a number of ways. For example, it’s possible to prevent yourself from getting AIDS by not having unprotected sex with someone who carries HIV.