Download Types of Pathogens

Infection Control
Infection Control
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Direct correlation
between exposure to
microorganisms and
disease
Types of Microorganisms
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Pathogens
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Any disease causing microorganisms
Non-pathogens
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Normal body flora
Beneficial:
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maintaining body processes
food production

Yogurt, sour cream, beer, bread
Types of Microorganisms

Saprophytes
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Live on dead matter or
tissues
Types of Pathogens
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Fungi:
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Molds and yeasts
Skin infections:
 Athlete’s foot
 Ringworm
 Thrush
Types of Pathogens
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Protozoa:
Only group of microbes
classified as animals
Types of Protozoa:
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Trichomonas vaginalis
Malaria
African sleeping
sickness
Types of Pathogens
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Viruses:
Obligate intracellular
parasite
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Cannot reproduce unless
inside host cell
Receives nutrients from
host cell
Not susceptible to
antibiotics
Causes:
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Varicella (chickenpox)
Common cold
Herpes
Bacteria
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Simple one celled plants
that multiply rapidly
Bacilli
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Rod-shaped
Have ability to form
spores-a protective hard
“shell” protects daughter
cell
Cause:
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Tuberculosis
Whooping cough
Hemorrhagic fever
Shapes of Bacteria
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Cocci
Round shaped
Diplococci-occur in pairs
Cause:
 Gonorrhoea
Streptococci-occur in chains
Cause:
 Strep throat
Staphylococci-occur in clusters
 most common bacterial
infection in humans
 Cause of nosocomial
infections
 Wound infections
 Toxic shock syndrome
Spirals

Spirilla
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Spiral or corkscrew
shaped
Causes:
 Syphilis
 Cholera
Factors Required for
Microbial Growth
Factors required for microbial
growth

Warm environment
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Darkness
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Body temperature
Many killed by sunlight
Source of food
Moisture and….
Factors required for microbial
growth

Varying oxygen needs

Aerobic bacteria
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Live and reproduce in presence of oxygen
Anaerobic bacteria

Live and reproduce without oxygen
How Microorganisms
Cause Disease
How microbes cause disease

Toxins

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Allergic reaction

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poisons
Runny nose, watery eyes, sneezing
Cell invasion

Invades living cells and destroy them
How Microorganisms
Are Spread
How Microorganisms are spread
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Direct contact
 Directly from one person
to another
 Sex, kissing, touching
Indirect contact
 From inanimate object to
person
Airborne
 Droplets from sneezing
and coughing
 Droplets of blood and
body fluids
Insects and pests
The Chain of Infection
1st Link- The Infectious Agent
Any pathogen
2nd Link- The Reservoir

Organism or
environment where
infectious agent resides
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People
Equipment
Water
Carrier Host
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Shows no outward
signs/symptoms of
disease, but capable of
transmitting the disease
3rd Link- Portal of Exit
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Route of escape of
pathogen from reservoir
Examples:
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respiratory tract
gastrointestinal tract
genitourinary tract
breaks in skin
4th Link- Route of Transmission
• Method by which pathogen gets from reservoir to new
host
• Direct contact:
• Sexual contact
• Contact blood/body fluids
• Indirect contact:
• Objects to person
• Airborne
• Insects and pests
5th Link- Portal of Entry
• Route which pathogen enters new host
• Examples:
• Respiratory tract
• Gastrointestinal tract
• Genitourinary tract
• Mucous membranes
• Breaks in skin
6th Link- Susceptible Host
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Organism that is at risk for infection
Organism with weakened immune system
Examples:
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AIDS pts
Pts on chemotherapy
Transplant pts
Elderly and very young
Burn pts
Interrupting the Chain of Infection
The Infectious Agent
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Early recognition of infection
Pathogen Identification
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Antibiotics
Reservoir Host
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Standard Precautions
Clean equipment
Clean environment
Healthy Employees
Portals of Exit
• PPE
• Gowns,
• Gloves,
• Protective clothing
• Handwashing
• Control secretions
• Waste disposal
Route of Transmission
• Standard Precautions
• Handwashing
• Proper disposal of contaminated objects
• Covering mouth & nose when coughing or
sneezing
• Food handling
Portals of Entry
• Standard Precautions
• Handwashing
• Proper disposal of needles or sharps
• Sterile technique
Susceptible Host
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Immunization
Good nutrition, exercise, rest
Recognize high risk patients
Remember--breaking the chain of
infection is the responsibility
of each health professional.
Hand Washing Tips
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Sink is considered contaminated
Use warm water
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Liquid soap preferred
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less damaging to skin
Friction, sudsing action & alkalinity of soap
bar soap and dish are contaminated
Keeping fingertips pointed downward
Wash palms, backs, sides, between fingers, under
and around nails, 2 in up arm
1 ½ to 2 min
When Hands Should Be Washed
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Beginning and end of shift
Between patients
After removing gloves and other protective
wear
When Hands Should Be Washed
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When visibly contaminated with blood or
tissues
Before leaving the patient area
Before and after eating, applying makeup,
using the bathroom, handling contact lenses,
handling equipment
Time for

Handwashing Video
Let’s Wash Our Hands!
OSHA standards
Regarding Blood-borne
Pathogens
Standard Precautions

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Developed by the CDC
Applied to all clients regardless of diagnosis
and infection status
Use when performing procedures requiring
contact with blood, body fluids, mucous
membranes or contaminated items.
Aseptic Techniques

Medical asepsis or clean techniques
designed to prevent spread of disease
Aseptic Techniques

Antiseptic

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Bacteriostatic substances
that inhibit the growth of
bacteria
Can be used on the skin

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Alcohol and iodine
Disinfectant
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Bactericidal substances that
kill bacteria and most
viruses
Cannot be used on the skin
10% bleach, chemicals,
boiling
Aseptic Techniques
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Sterilization
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Process destroys all
microbes including
spores
This includes steam or
gas under pressure,
radiation and chemicals
using an autoclave
Aseptic Techniques
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Surgical asepsis
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The use of all levels of aseptic techniques to prevent
introduction of harmful microorganisms into the patient
Aseptic Techniques
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Surgical asepsis
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Be aware of the sterile field
Draped in blue
Remember:
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Sterile to sterile = sterile
Sterile to unsterile = unsterile
Sterile to unsure = contaminated
Isolation
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Used when patient infected with a
communicable disease
Protects: HCW, other patients, visitors,
community
Use PPE
Types of Isolation
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Airborne
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Infections spread through
air by small droplets
containing pathogens
Ex: Tuberculosis,
Varicella (chickenpox)
PPE:
 surgical masks &/or
HEPA-filter masks
 Negative pressure room
Types of Isolation
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Droplet
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Infections spread through
air by large droplets
Ex: Pertussis, Influenza
PPE:
 surgical masks w/in 3 ft
of patient
 Glove for environmental
contact
Types of Isolation
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Contact
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For patients who are
infected or colonized by
a pathogen that spreads
by direct contact
Ex: antibiotic resistant
bacteria, RSV, Hepatitis
A
PPE:
 gloves, gown when
entering; remove before
leaving
Types of Isolation
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Reverse
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Protects patients from pathogens healthcare
provider or visitors may have
Used when patient immune system is suppressed
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AIDS pts
Chemotherapy pts
Burn pts
Transplant pts
The End
Asepsis Questions
1.
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6.
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8.
9.
10.
Describe your condition when “fit & well”.
What kind of symptoms indicate the presence of disease?
What is your experience of methods used to fight disease?
Give examples of diseases caused by living organisms.
Why do people in developing countries suffer more than in
developed countries?
List the four major groups of pathogens.
Describe how bacteria play a beneficial role.
Describe environmental factors influencing how bacteria grow.
Explain how viruses differ from bacteria.
Explain why viruses are spread so easily and are so hard to get
rid of.