Infection Flashcards
Infection
invasion of the body tissues by microorganisms with the potential to cause illness or disease
Diseases
exist when microorganisms cause a detectable alteration in function
Pathogens
microorganisms that cause diseases
Body’s natural defenses
intact skin and mucus membranes resident bacteria cilia and phagocytes tears high acidity (low pH)
intact skin and mucus membranes
1st line of defense, stops microbes from entering body
resident bacteria
lives on the body, prevents other harmful microbes from growing (microbial antagonism)
cilia and phagocytes
cilia filter and trap microbes and foreign particles in the upper respiratory tract
phagocytes ingest foreign material in alveoli (alveolar macrophages)
tears
flush organisms out of eyes
high acidity (low pH)
low pH deters microbial growth in stomach and vaginal area
Factors increasing susceptibility of infection
age heredity stress nutrition treatments/tests medications preexisting diseases
Age’s effect on susceptibility to infection
very young and very old at higher risk for disease
Heredity’s effect on susceptibility to infection
can play role with genetic predisposition to diseas
Stress’s effect on susceptibility to infection
increases blood cortizone which decreases inflammatory response and hampers the body’s ability to fight infection
Nutrition’s effect on susceptibility to infection
inadequate nutrition can impede the creation of antibodies
Medication’s effect on susceptibility to infection
may decrease production of wbc’s; decrease inflammatory response; destroy normal flora
6 links of the chain of infection
infectious agent reservoir portal of exit from reservoir means of transmission portal of entry susceptible host
Infection stages
incubation period
prodromal stage
acute stage
convalescent stage
Incubation period
pathogen begins replicating but doesn’t cause symptoms; can last hours to years
Prodromal stage
generic symptoms appear
Acute stage
maximum impact, specific symptoms appear, pronounced damage done to body tissues
Convalescent stage
infection contained; pathogen eliminated; tissue damage repaired
Normal white blood cell count
4,000-10,000 cells per microliter
White blood cell count below 4,000
leukeopenia
White blood cell count above 10,000
leukocytosis