Even though only approximately 25% of the patients seen by US physicians each day have infectious diseases, it is estimated that 8 out of every 10 deaths in the world are related directly or indirectly to an infectious disease. Diseases that are not communicable and not contagious are called intrinsic. Intrinsic means "from within." What categories of diseases are considered to not be infectious and related to microbes? One group would be hereditary diseases. Hemophilia or the inability of the blood to clot properly is one example of an inherited non-contagious disease. Diabetes and goiter are examples of non-infectious glandular diseases. Dietary related diseases are not contagious. You would not expect to catch ricketts or scurvy. Cancers are usually not directly related to microbes and are not considered to be contagious. Stress related diseases, heart murmurs, hardening of the arteries, varicose veins, as well as auto-immune diseases like rheumatoid arthritis and lupus are also examples of intrinsic diseases.