Infections in Healthcare
and Medical Asepsis
Infection
• Infection - invasion of the body by pathogenic
microorganisms
• Examples of microorganisms that can become
pathogenic (cause disease) – bacteria, virus,
fungi, protozoa …
• Local infection - one body part
• Systemic infection - whole body
• The passage of micro-organisms from one person to
another
Cross-Infection
• Passage ofCross-Contamination
microorganisms from one person or
inanimate object to another
Most common infections
• Respiratory tract infections (cold,
pneumonia, bronchitis, influenza)
• Urinary tract infections (UTIs)
• Gastrointestinal infections (nausea or
diarrhea)
• Skin infections (wound or IV site
infection)
Infections in Healthcare Settings
• Nosocomial infection: infection acquired
after admission to a health care facility
- microbes can enter body through
equipment used in treatments,therapies
and tests (equipment must be free of
pathogens)
The Chain of Infection
Chain of Infection
1) Infectious Agent (Pathogen): a microbe that is capable of
causing disease
2) Reservoir: the environment where the pathogen lives before
it infects
3) Portal of Exit: the path by which the pathogen leaves the
reservoir
4) Mode of Transmission: how the pathogen travels from the
portal of exit to the next reservoir or host
5) Portal of Entry: where the pathogen enters the new host’s
body
6) Susceptible Host: person at risk for infection
Microbe
• A living creature that is too small to be seen with
the naked eye
Normal Flora
Microbes that naturally live and grow in a
certain location - they are harmless or even
beneficial when they are in or on their natural
location
1st STEP IN THE CYCLE OF
INFECTION
INFECTIOUS AGENT
Pathogen
• Disease-causing
micro-organisms.
• A small number of
microbes are
pathogenic.
Bacteria
• A one-celled microbe. Beneficial bacteria can
help to sustain life and harmful bacterial can
cause illness or death. Most bacteria are
beneficial and help by fighting pathogenic
microbes (infection causing)
• There are about 300 different types of
bacteria in our mouth alone!
Bacteria
Naturally occurring single-celled
microbes that multiply rapidly
infections caused by bacteria are usually
treated with antibiotics
Aerobes
• A type of bacteria that requires oxygen to grow (ie.
staphylococcus species)
Anaerobes
• A type of bacteria that grow in the absence of
oxygen and are destroyed by oxygen
(ie. clostridium – botulism)
Facultative Anaerobes
• Organisms that can grow in either the presence or
the absence of oxygen.
(ie. listeria and e coli)
Bacteria Examples
E. Coli
Listeria
Bacteria Examples
E. Coli
May, 2000
Bacteria Examples
2008
Listeria
Virus
• A type of infectious agent that
is not bacterial.
• Viruses are very tiny and must
get inside a cell in order to
grow and multiply.
• They are very resistant to
death and are capable of
mutation.
Viruses
Non-living microbes that grow ONLY
inside living cells
They take over a cell’s machinery to
produce new virus particles
Antibiotics are NOT effective against
viruses
Some viral diseases can be prevented by
vaccination
Viruses
Herpes Virus
Human Papillomaviru
Fungi
Plants that lack chlorophyll,
such as mushrooms, yeasts,
and moulds.
Fungi
Microbes that live ONLY on organic
matter (i.e. Plants or animals)
Certain types of yeasts and moulds are
common fungi that can be pathogens
Fungi
Athlete’s Foot
Oral Fungus
Protozoa
• Single-celled, microscopic
animals without a rigid cell
wall.
• They cannot live on their own
as they require a vector to be
spread from one place to the
next.
2nd STEP IN THE CYCLE OF
INFECTION
HOST/RESERVOIR
Host/Reservoir
• A living organism from
which a foreign organism
obtains nourishment and
protection.
3RD STEP IN THE CYCLE OF
INFECTION
PORTAL OF EXIT
(Think openings of/on the body)
4th STEP IN CYCLE OF INFECTION
MODES OF TRANSMISSION
Modes of Transmission
• Contact : physical touch (direct or indirect)
• Droplet: microbes are spread short distances (less
than 1 meter) in the air by droplets – coughing,
sneezing and talking
• Airborne: microbes are transmitted long distances
(greater than 1 meter) by air currents
• Vehicle: microbes are transmitted by a
contaminated source (vehicle) – ex. food, water,
medication and invasive medical equipment.
• Vector-borne : insects or pests transmit microbes
to humans
5TH STEP IN THE CYCLE OF
INFECTION – PORTAL OF ENTRY
PORTAL OF EXIT
(Think openings of/on the body)
6TH STEP IN THE CYCLE OF
INFECTION
SUSCEPTIBLE HOST
(Those who are prone to being infected)
Factors that increase the risk of
infection:
•
•
•
•
•
•
•
Young and old are at risk
Poor nutrition
Lack of sleep
The presence of disease or illness
Certain medication
Invasive procedures
Open wounds
Preventing infections in healthcare
settings:
• Medical asepsis
• Isolation precautions
• Surgical asepsis
Medical Asepsis
• State of being free of pathogens (asceptic
technique reduces the number of microbes)
• Prevents the spread of microbes from one
person/place to another person/place
• Breaks the chain of infection
Asceptic Practices
•
•
•
•
•
Hand Washing
Sanitizing
Disinfection
Sterilization
Controlling reservoirs, portals of exit/entry,
transmission, and protect the susceptible host
• Wearing your PPEs (gloves, masks, protective
apparel, eye protection, face shield)
• Proper disposal and bagging of PPEs
OSHA
• Federal regulations related to infection control and
asepsis were developed by the Department of
Labor’s Occupational Safety and Health
Administration (OSHA)
• These laws protect health-care workers from health
hazards on the job, particularly from accidentally
acquiring infections and health hazards patients and
any other people who may come into the medical
office
The following must be discarded in a
biohazardous waste container
•
•
•
•
•
blood products
body fluids
human tissues
Vaccines
table paper, linens, towels, and gauze with body fluids on
them
• Used scalpels, needles, sutures with needles attached, and
other sharp instruments
• Used gloves, disposable instruments, cotton swabs, and
disposable applicators
OSHA laws ensure
• That proper measures are taken to prevent
infection
• Provide a margin of safety,
• Ensure that a medical facility meets at least
the minimal criteria for asepsis
• These laws include: requirements for training
personnel, keeping records, housekeeping,
wearing protective gear
OSHA divides tasks into 3 categories
• Category I – tasks that expose a worker to
blood, body fluids, or tissues or those that
have a chance of spills or splashes. *These
tasks always require specific protective
measures
• Category II – minimal risk of exposure ex.
administering nose drops (hand washing)
• Category III – tasks that do not require any
special protection (ex. talking to the patient)
Standard vs Universal Precautions
• Standard Precautions are used in hospitals
• Universal Precautions are used in medical
offices
What is WHMIS ?
The Workplace Hazardous Materials
Information System (WHMIS) is
Canada's hazard communication
standard.
What are the main parts of WHMIS?
The main components of WHMIS are:
hazard identification and product classification
labeling
material safety data sheets, and
worker training and education
Why was WHMIS created?
It was created in response to the
Canadian workers' right to know about
the safety and health hazards that may
be associated with the materials or
chemicals they use at work.
The 6 WHMIS classes:
1.
Compressed gas
2.
Flammable and Combustible
material
3.
Oxidizing material
4.
Poisonous and Infectious
materials
– Materials Causing Immediate and
Serious Toxic Effects
– Materials Causing Other Toxic Effects
– Biohazardous Infectious Material
5.
Corrosive material
6.
Dangerously Reactive
material