Host-Microbe Interactions Flashcards
Tb is an infection of a facultative _____ bacterium.
intracellular
What is active entry?
invading the host
What is the entry stage?
the 2nd step of infection; how the agent enters the host
What is the damage stage?
the 5th stage of infection; how is damage caused by the agent; virulence factors
_____ is a toxin-mediated disease; it lives intracellularly.
Cholera
What factors affect the microbiome, causing it to vary among individuals?
- diet 2. antibiotics 3. anatomic abnormalities (blind loop syndrome) 4. genetics
What is an important mechanism of microbial colonization?
adherence
What is the multiplication stage?
the 4th phase of infection; how the agent multiplies in the host; growth rates must exceed clearance
What is an infectious disease?
disease caused by an infection with a microbe
Microbes that can cause disease in normal hosts are ____.
frank pathogens
Why is the microbiome important?
- organ/tissue differentiation 2. production of vitamins 3. biochemical conversions 4. competes with pathogens for colonization of body surfaces
______ causes acute inflammation and lives extracellularly.
Pneumococcal pneumonia
Cholera is a _____-mediated disease; it lives _____.
toxin; intracellularly
Normal body flora are found in the ____, _____, ____, and _____.
skin, oropharynx, large intestine, vagina
_______’s pathology is mediated by an immune response.
Rheumatic fever
What is pathogenicity?
ability to cause disease or host damage
What are the resident microbes of the skin?
- staph 2. corynebacteria 3. enteric bacilli
_______ is an important first step in the pathogenesis of many microbial infections.
Colonization of body surfaces
Microbes that cause disease in immunocompromised hosts but not usually normal hosts are _____.
opportunistic pathogens
What is infection?
the process of a microbe entering into a relationship with the host; may or may not cause a disease
______ is an infection of a facultative intracellular bacterium.
Tb
What is the outcome stage?
the 6th and final stage of infection; who wins the battle? do they coexist? consequences?
____ and ____ contribute to the outcome of an infectious disease.
Microbial and host
What is the encounter stage?
the first step of infection; how the agent meets the host; dose, route, endogenous or exogenous
What is the spread stage?
the 3rd step in infection; how the agent spreads from the site of entry
What are the resident microbes of the vagina?
- Strep 2. Lactobacilli 3. enteric bacilli (clostridia, pseudomonas) 4. mycoplasma
What is adherence?
binding of microbial surface components to host receptors
Name an agent that inhibits the spread of microbes thru tissues.
coagulase
Pneumococcal pneumonia causes acute inflammation and lives _____.
extracellularly
What are the resident microbes of the oropharynx?
- Micro. strep 2. Lactobacilli 3. enteric bacilli (clostridia, pseudomonas)
What is virulence?
the degree of pathogenicity; capacity to cause damage
What are the resident microbes of the oropharynx?
- alpha-hemolytic strep 2. corynebacteria 3. Neisseria 4. H. bacteroides 5. Mycoplama 6. spirochetes
What are Koch’s Postulates? (4)
- specific microbes present in specific diseases 2. microbes can be isolated and grown in vitro 3. injections of microbes into animals reproduces disease 4. same specific microbes can be re-isolated from new lesions
Rheumatic fever’s pathology is mediated by _____.
an immune response
What is passive entry?
via injection, bites, transfusion, organ transplants, etc
Name 3 factors that enhance the spread of microbes thru tissues.
- hyaluronidase 2. elastase 3. collagenase
What are the 6 stages of infection?
- encounter 2. entry 3. spread 4. multiplication 5. damage 6. outcome
What does exogenous mean?
from the environment
What is coagulase and how does it work?
an agent that inhibits microbe spreading thru tissues; promotes fibrin deposition to wall off and localize infections
What does endogenous mean?
from within (the normal flora)
