2.1 Innate Immunity Flashcards
Immune system
Cells and organs that contribute to immune defences against infectious & non-infectious conditions
Infectious disease
When the pathogen succeeds in evading and/or overwhelming the host’s immune defences
Roles of the immune system
Pathogen recognition
Containing/eliminating infection
Regulating itself
Remembering pathogens
Difference between infectivity and virulence
Infectivity: ability of microbes to invade cells
Virulence: ability of microbes to damage cells
List the different innate barriers to infection
Physical barriers
Physiological barriers
Chemical barriers
Biological barriers
Describe the biological barriers of the body
Normal flora
-non pathogenic microbes
-absent in internal organs/tissues
-strategic locations (mouth, skin GI tract)
Benefits of normal flora
-Compete with pathogens for attachment sites & resources
-Produce antimicrobial chemicals
-Synthesise vitamins
-Immune maturation
Examples of normal flora that inhabit the skin (condition it can develop)
Staphylococcus aureus
Staphylococcus epidermidis
Streptococcus pyogenes (Scarlett fever)
Candida albicans (Vaginal & organ thrash)
Examples of normal flor that inhabit the mouth&nasopharynx
Streptococcus mutans
Streptococcus peneumoniae (pneumonia)
Neisseria meningitidis (meningitis)
Haemophilus species (meningitis)
Examples of normal flora that inhabit the GI tract
E.Coli (Food poisoning, diarrhoea)
How is normal flora displaced from its normal location to sterile location
Breaching the skin integrity
Fecal-oral route
Fecal-perineal-urethral route
Poor dental hygiene/dental work
What groups of people are at most risk of infection
Elderly persons (>65 yrs)
Children (>5 yrs)
Pregnant women
Who are high-risk patients for serious infections
Asplenic patients
Patients with damaged/prosthetic valves
Patients with previous infective endocarditis
