Download Infection Unit 12

Infection Unit 12
Adonis K. Lomibao, R.N.
12/19/11
Objectives
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Spell & Define key terms
Identify most common microbes &
characteristics
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List links in chain of infection
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List the ways infectious disease are spread
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Name & describe 5 serious diseases
Objectives Cont.
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Identify cause of important infectious disease
Define spores & explain how they differ from
other pathogens
Describe common treatments for infectious
disease.
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List natural body defenses against infection
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Explain why patients are at risk for infection.
Introduction
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Organisms-living beings
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Microorganisms or microbes-tiny organisms
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Nonpathogens-microbes that do not cause
disease
Pathogens- disease causing microbes
-Grow best at body temp, limited light,
moisture,food supply, & oxygen.

Infection- pathogens invade the body & cause
disease.
Microbes
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4 types
-Bacteria
-Viruses
-Fungi
-Protozoa
Bacteria
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Simple one-celled organisms
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Named according to shapes & arrangement
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Shapes:
-Coccus- round or spherical
-Bacillus-straight rod
-Spirillum-spiral, corkscrew,slightly curved
Bacteria Cont.

Arrangements:
-single
-pairs:diplo-
-chains:strepto-clusters:staphylo
Colonies-groups of growing bacteria
Fungi
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2 kinds:
-yeast:single cell budding forms of a fungus.
Can affect mouth, skin, & feet
-molds:can cause infections in the lung
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Parasite: an organism that lives in or on
another organism without benefiting the host.
Immuno-suppressed patients at risk
Virus

The smallest microbe

Come in a variety of shapes

Classified by:
-type of DNA or RNA
-clinical properties

Common viruses include:
Hepatitis,Herpes,HIV/AIDS,chickenpox,
influenza, common cold,p.156
Protozoa

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Once-celled organisms that live on living
matter
Classified by how the move...i.e. Whiplike
tails, hairlike projections.
i.e. Malaria
S&S:Diarrhea, Dysentery(lower bowel
infection), encephalitis
The Chain of Infection
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Certain conditions exist for infection to occur

COI Includes:
-Causative agent:pathogen that causes disease
-Reservoir or source: where the pathogen can
live & reproduce
-Portal of exit: manner in which the pathogen
leaves the body
COI Cont.
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Method or mode of transmission:manner in
which the pathogen is carried to another
person
Portal of Entry: manner in which the pathogen
enters the body
Susceptible host: a person who will become ill
from the entry of pathogens into the body
Object of Infection control is to DISRUPT the
chain of infection!!
Causative agent


Microorganism that can produce the disease
in humans
Most common causes:
-Bacteria
-Viruses
-Fungi
-Protozoa
Reservoir or source

Where pathogens can survive

May or may-not multiply in reservoir

Four common reservoirs:
-Humans
-Insects & animals
-Environment
-Fomites:objects that can be contaminated with
infectious material that contains the microbe.
Human Reservoirs

2 types;
-Cases:people with acute illness with S&S
-Carriers: persons who can give a disease to
others. May not have S&S or know of
infections.
Portals of Entry

Organisms enter through:
-breaks in skin or mucous membranes
-respiratory tract
-genitourinary tract
-gastrointestinal tract
-circulatory system
-transplacental
Portals of Exit
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Leave the reservoir of host through body
secretions
POE Include:
-excretions or resp. tract or genital tract
-draining wounds
-urine
-feces
-blood & body fluids
-Saliva & Tears
Transmission of Disease

Spread of infectious organisms may happen in
3 ways:
-Airborne Transmission
-Droplet Transmission
-Contact Transmission
-Vector Transmission
Host
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The person who harbors infectious organisms.
Person does not have enough resistance to
agent
Infection develops when organism penetrates
the body, begins to multiply, & causes damage
Risk factors are conditions that indicate a
problem may develop.
Types of Infections

Local: confined to one area..i.e. Boil or
abscess
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Generalized: i.e. pneumonia in the lungs
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Systemic: widespread through bloodstream
Body Flora
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Microbes that live in and on our body surfaces

Healthy individuals lives in harmony with flora
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Balance may be disturbed by:
-pathogens
-normal flora that become pathogenic
-flora from on body area to another
-drugs that upset balance and allow one to
flourish
How Pathogens Affect the Body
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Microbes act in different ways to produce
disease:
-Attack & destroy cells they invade
-produce toxins that harm the body
-cause sensitivity responses called allergies
Body Defenses
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Intact skin
Mucous membranes-sticky & trap foreign
materials
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Cilia-propel mucus out of body
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Coughing & sneezing
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Hydrochloric acid

Tears
Internal Defenses
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Fever
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Phagocytes
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Inflammation
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Temperature
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Immune response
Immunity

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The ability to fight of disease caused by
microbes
Antigen- pathogenic microbe that enters the
body
Antibodies- provide immunity to disease
caused by that antigen
Immunization: Vaccines protect against
specific pathogens
Immunosupression: the body's immune
system is inadequate...more likely to develop
infections.
Bacterial Infections
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Diagnositic: Culture & Sensitivity
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Antibiotic-antibacterial drug.
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Common bacterial infections include:
-MRSA & VRE
-Tuberculosis
-Streptococcus A
-Escherichia coli
-Pseudomembranous Colitis(C. Diff)
Spores

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Microscopic reproductive bodies that are
responsible for the spread of some diseases.
Can survive in a dormant form until conditions
are ideal for reproduction
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Difficult to eliminate

Examples:
-Norovirus
-C. Difficile
Viral Infections
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Examples:
-Shingles
-Influenza
-AIDS
-Hantavirus
-Sever Acute Resp. Syndrome
-Smallpox
Parasites
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Survive by feeding off another human or
animal
Examples:
-Head Lice:spread by direct contact.--Nits(eggs)
-Scabies:caused my microscopic mite.Spread
by in/direct contact
-Bedbugs:bites cause painful rash
Self-Care
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Healthy diet
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Get enough sleep
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Keep your body clean
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Live in a clean environment
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Avoid smoking & substance abuse
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Learn how to cope with stress