Infections pt.1 Flashcards
What are these terms:
- Communicability
- Infectivity
Communicability: Ability to infect person to person
Infectivity: Ability to multiply in person
What are these terms:
- Virulence
- Pathogenicity
Virulence: Capacity to cause severe disease
Pathogenecity: Ability to produce disease (dependent on communicability and infectivity)
What are these terms:
Toxigenicity
Toxigenicity: Ability to produce toxins
What are the differences in bacteremia and septicemia?
Bacteremia: Presence of bacteria in blood
Septicemia: Growth of bacteria in blood
What can septicemia lead to?
Septic (endotoxic shock)
Gram negative bact. release endotoxins:
Widespread vasodilation that leads to lots of plasma in tissues
What do exotoxins do?
Enzymes that :
- damage plasma membrane of host cell
- Inactivate protein synthesis enzymes
What do endotoxins cause?
Activate the inflammatory response and cause fever (progens)
How do latent virsuses work?
Hide in host cell
- Activate by stress, hormones, and disease
Why can the flu cause repeat infections?
Undergoes antigenic variation:
Antigens undergo yearly changes
Diseases caused by fungus are called:
Where do they infect?
Mycoses
Can be superficial, deep, or opportunistic
Pathogenic fungus that grow on skin, hair or nails:
The diseases are named:
Dermatophytes
Named tineas (ringworms)
Why are fungal infections so hard to defeat?
Adapt to host environment:
- Temperature variations, require low oxygen
- Suppress the immune system
The most common cause of fungal infections:
Where are they typically found:
Opportunistic fungi: Candida albicans
found in normal microbiome
What types of infections can Candida cause?
- Localized
- Disseminated (systemic) if immunocompromised
One species benefits at the expense of the other:
Symbiotic parasite
How do parasites typically infect?
- What microbes are included in parasites?
Spread human to human via vectors
- Unicellular protozoa
- Eukaryotic helminths
What is the hallmark sign of infections?
What causes this?
Fever
- Exogenous pyrogens: Cause body to produce endogenous pyrogens (interleukins)
When are fevers beneficial?
Low-grade fevers are beneficial and natural
High-grade fevers may require treatment
Vaccines that use weakened, live viruses are:
Risks from these vaccines include:
Live-attenuated vaccine
- Immunocompromised individuals can develop infection
Non-attenuated vaccines usually require:
Boosters
What is passive immunotherapy?
Example?
Immunity is given to person:
- Monocolonal antibody treatment
Antimicrobials can be these 2 types:
-
Bacteriostatic
- Inhibits growth
-
Bacteriocidal
- Kills microbe
Antimicrobial resistance is caused by:
- Lack of compliance with use
- Overuse when not needed
What are secondary immune deficiencies?
Acquired deficiencies:
- Physiological condtions
- Stress
- Trauma
- AIDS
What is AIDS?
What is it caused by?
Secondary immune deficiency caused by HIV:
HIV destroys body’s CD4+ T-helper cells
What are the common causes of HIV?
Blood-borne (IV, needles..)
Sexual activity
