The invasion of the body by microorganisms or viruses can cause disease. Microorganisms that cause infection include bacteria, viruses, protozoans, and fungi.
Immunity: The immune system that protects our body from diseases and infections. It's the bodily system that produces the immune response to defend your body from foreign cells, substances, and tissues. The immune system includes various parts of the body including the spleen, thymus, lymph nodes, special deposits of lymphoid tissue (such as those in the gastrointestinal tract and bone marrow), and macrophages, lymphocytes including the T cells, and B cells, and antibodies.
Inflammation: The inflammatory response can be chemical, physical, and biological agents, including exposure to excessive amounts of sunlight, mechanical trauma, x-ray, and radioactive materials, extremes of heat and cold, corrosive chemicals, or by infectious agents can produce inflammation, infection and inflammation are not synonymous.