Host-Microbe Relationships Flashcards
Give Term:
The close association and interaction of two dissimilar organisms living together.
Symbiosis
Give Term:
Those microorganisms which are normally and consistently found in or on the body in the absence of disease.
Normal Flora
Name three considerations/characteristics regarding Normal Flora.
- Resident vs. Transient Flora
- Nature and variety of microbes are often distinctive for different regions of the body
- Normal flora of one area may cause infection in another region of the body
Define: Commensalism
Association between organisms in which one is benefitted and the other is neither benefitted nor harmed
Define: Mutualism
Both the microbe and host derive benefits from the relationship
Give the term:
Disease traits of the resident flora are demonstrated only when normal host-microbe relationship is altered.
Opportunism
Name some ways host and microbe relationship might be altered?
- Prolonged antibiotic therapy alters flora
- Traumatic injury, surgery
- Immunological compromise
- Hormonal or chemical changes
Define: Parasitism
Symbiotic relationship in which a microorganism lives in or on a host at the expense of the host
Give the Term:
A carrier of microbes from one host to another.
Vector
Name some vectors.
- Insects and other animals
- Inanimate articles (fomite), e.g. personal items, eating utensils, tools, hospital instruments, food, water, etc…
Give the term:
The growth and spread of a pathogen in or on a host resulting in injury to the host tissue.
Infectious Disease
Define: Pathogen
A microbe capable of causing disease by invading tissues, producing toxins, or both
Define: Virulence
The degree of pathogenicity
Regarding Virulence what two items are considered?
Infectivity & Severity
Define: Infectivity
How easily the microbe survives the normal host defenses and establishes infection
