Study Guide: Microbiology 
Microbiology, Test 3 Study Guide Chapters 14, 15, 16 and 17 Chapter 14 This chapter is about the principles of disease and epidemiology. Epidemiology – the science that studies when and where diseases occur and how they are transmitted. CDC, Atlanta, tracks and traces diseases. ONE World (the idea that it’s all in one place, it could happen anywhere; locally, states, large counties track the incidences and occurrences of disease) Pathology – scientific study of disease. Pathogenesis – the manner in which a disease develops Pathogen – disease causing organism (from worms to prions, viruses, or bacteria) Pathogenicity – the ability of a microorganism to cause disease by overcoming the defenses of a host Pathologist – one who examines diseased tissue to find out the cause and eventually the prevention Etiology – the cause of the disease, virus, bacteria, chemical Virulence – the probability that a microbe will cause disease Disease – infection which results in a change from a state of health Infection - the invasion or colonization of the body by pathogenic MCOs ; not normal fluora, Infectious disease specialist treats the disease Normal Microbiotica or normal flora. Pick up shortly after birth, canal, inoculated by people and surroundings; no two are the same; lives on us at all times, harder to wash away than transient flora symbiotic relationship – two or more organisms living together (fungus and algus=lichen) Mutualism - all benefit (E. Coli makes vitamin K) Commensalism – one benefits, the other is not harmed (cattle, birds, grass) Parasitism - one benefits, the other is harmed (worms or protozoan, virus) Transients - temporary residents, moving a lot, 1