Constitutive Defenses Barriers to entry – See Schaechter text, Table 6.1 Mucous membranes—covered by protective layer of mucus – Mechanical and chemical barrier that allows proper functioning
Choosing an Animal Model Pathogen may not affect animal at all -ORmay give different symptoms Given disease may have a number of animal models, none of which fully satisfies characteristics of disease
General aspects – Remember definition: organisms frequently found on or within body of healthy individuals – Most are bacteria, but some are viruses, fungi, and protozoa
