Chapter 11 - Infection control Flashcards
Pathogen types
Bacteria VIruses Fungi Prions Parasites
Define virulence
Ability to invade and injure host
Describe Herpes Zoster
viral infection that can erupt years after chickenpox exposure. - invades nerve tract
Two types of immune defenses -
Nonspecific innate AND Specific adaptive
Two types of Nonspecific innate immunity?
Native immunity AND passive
Define native immunity?
Phagocytic cells, complement, and inflammation immediately respond to antigen exposure.
Occurs even if no previous exposure
Define passive immunity?
Antibodies given from external source (breastmilk)
What is the body’s 1st line of defense against pathogens?
Skin
Define specific adaptive immunity?
Body makes antibodies in response to a particular antigen.
What are 4 aspects of an active specific adaptive immunity?
- Requires time to react to antigens
- Provides permanent immunity
- Involves B/T lymph
- Provides GMADE Abs
Routes of portal of exit?
Respiratory, GI, GU, Skin, membranes, Body fluids, transplacental
Organisms associated with GU portal of exit?
Hep A, E. Coli, HSV, HIV
Organisms associated with Skin/Membranes portal of exit?
HSV, Varicella
Organisms associated with Blood/body fluids portal of exit?
HIV, Hep B, Hep C
What are the 4 modes of transmission?
Contact
Droplet
Airborne
Vector
What are the 3 types of contact modes of transmission?
Direct - Person to person
Indirect - Object to person
Fecal/Oral - Handling food
What is the chain of infection?
Susceptible host Causative agent Reservoir Portal of exit Mode of transmission Portal of entry
What are the stages of infection?
Incubation
Prodromal stage
Illness stage
Convalescence
Define incubation?
Interval between entry and 1st symptom
Define Prodromal stage?
Interval between - general finding onset and distinct findings
The pathogen multiples at this point
Define convalescence stage?
Interval when acute findings disappear (days to months depending on INF)
What are the 3 stages of inflammation?
Local infection - Red, warm, swelling, TTP
Exudate - Org killed byproducts
Tissue healing/scarring
Describe 3 types of exudate?
Serous - clear
Sanguineous - contains RBCs
Purulent - contains WBCs/bacteria
Common Lab tests for infection?
CBC - WBC >10k
ESR - >20mm/hr
Positive culture
Common Dx procedures for infection?
Gallium scan
Radioactive Gallium citrate
Biopsy
XR, CT, MRI
Two tiers of isolation guidelines?
Standard precautions (tier one) Transmission precautions (tier two)
