Chapter 13 Infection & Disease Flashcards
infection
pathogenic m.o. penetrate host’s defenses and multiply
Infectious disease
Disruption of a tissue/organ caused by microbes or their products
normal microbiota
“normal flora”
m.o. normally present in and on body
Benefits of normal flora
Provide nutrients to host (vitamins)
Can break down food for host
Immune stimulation
Sterile body organs
Heart and circulatory system, liver, kidneys and bladder, brain and spinal cord, muscles, bone, ovaries/testes, glands, internal eye, sinuses, middle and inner ear.
Opportunistic pathogen
Causes disease in immunodeficient people w/another primary disease
Virulence factors
Microbial components that contribute to ability to cause disease in a susceptible host
The 4 portals of entry for microbes
Skin: abrasions, cuts, punctures
GIT: pathogens in food and drink
Respiratory: air spit
Urogenital: STDs, mucosa, unbroken skin
Pathogens during pregnancy and birth
cross placenta or during birth.
Toxoplasmosis Other Rubella Cytomegalovirus Herpes
Exotoxins
Secreted by living cell and targets specific tissues
ex Clostridium botulism
Endotoxins
Outer layer/LPS of gram- m.o. that causes fever, shock, vasodilation, diarrhea, and death
Systemic infection
Affecting the entire body
Focal infection
Localized infection
Mixed infection
Infection on viruses and bacteria
Acute infection
Short-lived infection
Symptoms
Subjective evidence of disease as sensed by the patient
ex feeling unwell
Signs
Objective evidence of disease as noted by an observer
Incubation
Time of initial contact with m.o. to first symptoms
Prodromal stage
Time of vague symptoms
ex general fatigue