Infection, Infectious Diseases, and Epidemiology Flashcards
Define symbiosis
To live together
Define symbionts
Members of a symbiotic relationship
Define mutualism
Symbionts benefit from their interaction
Bacteria in the human colon is an example of ______
Mutualism
Define commensalism
One symbiont benefits without significantly affecting the other
Staphylococcus on skin is an example of ______
Commensalism
Define parasitism
A parasite benefits while harming its host
Tuberculosis bacteria is an example of ______
Parasitism
What is an axenic environment?
An environment free of any microbes
The environment in which microbes colonize in the body without normally causing disease is called a ______
Microbiome
______ remain a part of the normal microbiota for most of a person’s life
Resident microbiota
______ remain in the body for only a few hours, days, or months, before disappearing
Transient microbiota
Do normal microbiota ordinarily cause disease?
No
Describe 4 different factors or conditions that would be expected to favor opportunistic growth
- Introduction of normal microbiota into an unusual site
- Immune system suppression
- Changes affecting microbial antagonism
- Stress
A ______ is a site where pathogens are maintained as a source of infection
Reservoir of infection
What are the 3 different kinds of reservoirs of infection?
- Animal reservoirs
- Human reservoirs
- Nonliving reservoirs
What is a zoonotic disease?
A disease that spreads naturally from animal hosts to humans
What are the 3 major human portals of entry for pathogens?
- Skin
- Placenta
- Mucous membranes
What is the parenteral route?
A puncture through the skin / GI tract
What is the function of adhesion factors (adhesins)?
Enable pathogens to bind to receptors on host cells
Any change from a state of health refers to ______
Disease / morbidity
Differentiate among symptoms, signs, and syndromes
- Symptoms - subjective characteristics of disease (felt by the patient)
- Signs - objective characteristics of disease (can be measured)
- Syndromes - a group of signs and symptoms
What does asymptomatic / subclinical refer to regarding disease?
Lack of symptoms allowing an infection to go unnoticed
Virulence refers to the degree of ______
Pathogenicity
What are virulence factors?
Traits that enable pathogens to cause disease
What role do hyaluronidases play in infection and disease?
They digest hyaluronic acid
______ is the ‘glue’ that holds animal cells together
Hyaluronic acid
What role do collagenases play in infection and disease?
They break down collagen
______ is the body’s chief structural protein
Collagen
What role do coagulases play in infection and disease?
They cause blood proteins to clot
Coagulases provide a ______ for bacteria
Hiding place
What role do kinases (staphylokinase and streptokinase) play in infection and disease?
They digest blood clots