Post on 25-Dec-2015
INFECTION CONTROL
Understanding the basic principles of infection control is essential for any healthcare worker in any field of health care.
Our essential question is: How are diseases transmitted and
what are the main ways to prevent disease transmission?
Principles of Infection Control
Microorganism (or microbe) – small, living organism that is not visible to the naked eye.
Found everywhere in the environment, including on and in the human body
Nonpathogens – microorganism that is not capable of causing disease
Pathogens – microorganisms that cause infection and disease
Microorganisms can be beneficial in one body system and pathogenic in another body system
EX: E. Coli – digestive system – normal flora
urinary system - infection
To grow and reproduce, microorganisms need: Warm environment - body temp ideal Dark environment Source of food Source of moisture Aerobic organisms require oxygen Anaerobic organisms live and reproduce in
absence of oxygen Human body is ideal supplier of all
requirements of microorganisms
Main Classes of Microorganisms
Bacteria Protozoa Fungi Rickettsiae Viruses Helminths
Group Work
Each group will be assigned a pathogen in which they will become experts on.
Describe pathogen How are they classified? If possible, describe their shape? What diseases does this pathogen
cause? What is some other interesting info you
would like to share?
Bacteria
Simple one-celled organisms Multiply rapidly Classified by shape and arrangement Cocci Bacilli Spirilla Antibiotics are used to kill bacteria
BacteriaCocci
Round or spherical in shape If occurs in pairs – diplococci Cause diseases such as gonorrhea,
meningitis, pneumonia If occur in chains – streptococci Causes diseases such as strep throat
and rheumatic fever If occur in clusters - staphylococci
BacteriaCocci (cont’d – Staphylcocci)
Most common pyogenic (pus-producing) microorganisms.
Cause infections such as boils, wound infections, and toxic shock.
BacteriaBacilli
Rod-shaped bacteria Occur singly, in pairs, in chains Many contain flagella (threadlike
projections similar to tails – allow to move)
Have ability to form spores (thick- walled capsules) when conditions for growth are poor.
In spore form, bacilli extremely difficult to kill
BacteriaBacilli (cont’d)
Causes diseases such as tuberculosis, tetanus, pertussis, botulism, diphtheria, typhoid
Bacteria(Spirilla)
Comma shaped and corkscrew shaped
Causes diseases such as syphilis and cholera
Application:
1. Divide paper in thirds2. Label the first column Cocci Bacteria,
second column Bacilli Bacteria, third column Spirilla Bacteria.
3. Draw a diagram of each type of bacterial shape indicating 4 types of cocci, 3 types of bacilli, and 3 types of spirilla
4. Label diagrams5. List at least 5 diseases caused by cocci
and bacilli, and 2 diseases caused by spirilla
Protozoa
One-celled animal like organism Usually found in decayed materials
and contaminated water, animal or bird feces, insect bites
Many contain flagella to allow them to move freely
Cause diseases such as malaria, amebic dysentary, trichomonas (STD) , African sleeping sickness
Protozoa (Malaria)
Fungi
Small, plant-like organisms Live on dead organic matter Yeasts and molds are 2 common forms Causes diseases such as ringworm,
athlete’s foot, thrush, yeast vaginitis Antibiotics do not kill fungi Antifungal medicines - expensive,
long course of treatment, may cause liver damage
Rickettsiae
Parasitic microorganisms (cannot live outside the cells of another organism)
Found in fleas, ticks, lice, and mites and transmitted to humans by the bites of the insects
Causes diseases such as Rocky Mountain Spotted Fever
Treat with antibiotics
Viruses
Smallest microorganism– visible only with electron microscope
Cannot reproduce unless inside another living cell
Spread from human to human by blood and other body secretions
Can be resistant to disinfectants Antibiotics not effective
Virus(cont’d)
Causes diseases such as common cold, measles, mumps, chickenpox, herpes, warts, influenza, polio
3 diseases of major concern to healthcare worker:
Hepatitis BHepatitis CAIDS
New and different viruses emerge constantly because viruses are prone to mutating and changing genetic information.
Viruses that infect animals can mutate to infect humans – often fatally
Examples: SARS (severe acute respiratory infection), West Nile Virus, monkeypox, Ebola
HIV and Flu Viruses
Viruses of Special Concernto the Healthcare Worker
Hepatitis B Hepatitis C AIDS
Hepatitis B
Caused by HBV virus Transmitted by blood, serum and other
secretions Affects liver – can lead to destruction of
liver cells Can remain active for several days in
dried blood Vaccine available – expensive – series of 3 By law, employers must provide vaccine
to healthcare worker for free
Hepatitis C
Caused by HCV virus Transmitted by blood or blood-containing
fluids No vaccine available Patients often asymptomatic or mild flu
symptoms Can cause liver damage Extremely difficult to destroy Can remain active for several days in
dried blood
AIDS
Acquired Immune Deficiency Syndrome
Caused by HIV (human immunodeficiency virus)
Suppresses immune system Cannot fight off cancers or infections
that would not normally affect healthy person
No cure No vaccine
Microorganisms need certain things to grow and reproduce: Most prefer a warm environment – body temp
Most prefer darkness Most need food Most need moisture
Aerobic organisms – are organisms which require oxygen to live
Anaerobic organisms – do not require oxygen
Microorganisms can produce toxins: Toxins = poisons Ex: tetanus produces a toxin that
damages the CNS (central nervous system)
Helminths
Multicellular parasitic organisms Called worms or flukes Transmitted to humans when
humans ingest the eggs or larvae in contaminated food, ingest meat contaminated with worms, or the worm penetrates the skin.
Examples of Helminths:
Hookworms – attach to small intestine and can infect heart and lungs
Ascariasis – live in small intestine and can cause obstruction of the intestine
Trichinella spiralis – causes trichinosis contracted by eating raw or inadequately cooked pork
Enterobiasis (pinworms) mainly affects young children
Hookworm in intestine
Hookworm beneath skin
ascriasis
Trichinella spiralis
4 Classifications of Infectious Diseases
Endogenous Exogenous Nosocomial Opportunistic
Endogenous - infection /disease originates in body . Ex: tumor, congenital abnormality
Exogenous – infection/disease originates outside body. Ex: pathogenic organisms that invade body
Nosocomial infection – infection acquired by an individual in a healthcare facility. Ex: staph
Opportunistic – occurs when the body’s defenses are weak. Ex: Kaposi’s sarcoma
Chain of Infection:
For diseases to occur and spread from one individual to another, certain conditions must be met… Chain of Infection
Causative agent Reservoir Portal of exit Mode of transmission Portal of entry Susceptible host
Causative Agent:
A pathogen: Bacteria Virus Fungi Protozoa Rickettsiae HelminthWhat causes the infection/disease?
Reservoir:
A place where the pathogen can live: Human body Animals Environment Fomites (objects contaminated with
infectious material) Ex: door knobs, linens, instruments, etc
Portal of Exit:
A way to escape from the reservoir where it has been growing urine Feces Saliva Tears Blood Draining wounds Mucous discharge
Mode of Transmission:
Way it can be transmitted to another reservoir or host where it can live. Direct person to person contact Direct contact with body secretion
containing pathogen Ex: contaminated hands Indirect contact such as food, air, soil,
insects, feces, clothing, instruments and equipment
Portal of Entry:
Way to enter a new reservoir or host Breaks in skin Breaks in mucous membranes Respiratory tract Digestive tract Circulatory system
If the defense mechanisms of the body are intact and functioning, a human can frequently fight off the causative agent and not contract the disease.
Susceptible Host:
Person likely to get an infection
Application:
Using your textbook, identify 8 Body Defenses that work to prevent a causative agent from entering the human body.
Give an example of each Identify how each defense
mechanism prevents the causative agent from entering the body
Body Defenses
Mucous membranes Cilia Coughing and sneezing Hydrochloric acid – in stomach Tears in the eye Fever Inflammation (WBC destroy
pathogens) Immune response (antibodies)
Scenario:
Flu is caused by the influenza virus. Anyone can get the flu, which is a viral infection that attacks the respiratory system including your nose, throat, bronchial tubes and lungs. You’re especially at risk if you’re older, have diabetes, chronic heart disease or an impaired immune system. Someone you know has the flu, coughs and sneezes and then you touch something they’ve handled. That’s why the flu spreads anywhere people congregate…schools, cruise ships, day cares, etc.
Identify the:
Causative agent Reservoir Portal of exit Mode of transmission Portal of entry Susceptible host
E. coli is short for Escherichia coli—a germ that causes severe cramps and diarrhea. E. coli is a leading cause of bloody diarrhea. The symptoms are worse in children and older people, and especially in people who have another illness. E. coli infection is more common during the summer months and in northern states.Healthy beef and dairy cattle may carry the E. coli germ in their intestines. The meat can get contaminated with the germ during the slaughtering process. When beef is ground up, the E. coli germs get mixed throughout the meat.The most common way to get this infection is by eating undercooked hamburgers. You can be infectedwith the E. coli germ if you don’t use a high enough temperature to cook your beef, or if you don’t cook it long enough. When you eat undercooked beef, the germs enter your stomach and intestines.
If any part of the chain of infection is eliminated, the spread of disease or infection will be stopped.
Healthcare workers must understand chain of infection to interrupt or break the chain and prevent spreading of disease.
Pathogens are everywhere ….preventing their transmission is an ongoing process
Ways to Break Chain of Infection
Contamination – organisms and pathogens are present
Aseptic techniques – maintaining cleanliness, and eliminating or preventing contamination
Examples of common aseptic techniques: Handwashing Good personal hygiene Disposable gloves Proper cleaning of instruments Thorough cleaning of environment
Levels of Aseptic Control
Antisepsis – antiseptics prevent growth of pathogens….not effective against spores or viruses. Can be used on skin (alcohol, betadine)
Disinfection – process that destroys or kills pathogens…sometimes effective against spores or viruses. Usually used on objects and not skin (disinfectants such as bleach)
Sterilization – destroys all microorganisms including spores and viruses (autoclave)
Application:
1. Draw the chain of infection2. Label each of the 6 sections of the
chain of infection3. Identify 3 ways to break each
section of the chain of infection
Bioterrorism
Bioterrorism is the use of microorganisms or biological agents as weapons to infect humans.
Major concern of biological agents used not only in wars, but also against unsuspected civilians (ex: mail attack with anthrax)
Could cause an epidemic and public health emergency
Every healthcare worker must be alert to the threat of bioterrorism
Application:
Discussion of high priority agents that have been identified as potential bioterrorism agents
Handwashing
Handwashing is the most important method used to practice aseptic technique.
Most effective way to prevent spread of infection.
Hands are perfect medium for the spread of pathogens.
Proper handwashing helps prevent and control spread of pathogens AND protects health worker from disease and illness.
When should you wash hands?
Before and after every patient contact
Anytime hands become contaminated during procedure
Before applying and immediately after removing gloves
CDC recommendations for handwashing: Regular handwashing – soap and water;
routine cleansing of hands when hands are visibly dirty or soiled with blood/body fluids
Antiseptic handwashing – antimicrobial soap and water; before invasive procedures, critical care units, specific organism transmission based precautions
Antiseptic handrubs – alcohol based hand cleaners – ONLY if hands are not visibly dirty and are not soiled with blood/body fluids
Principles of Handwashing
Soap Warm water Friction Clean all surface areas Point fingertips downward Use paper towels to turn faucet off
and on Clean nails also
Proper Handwashing Tips:
Soap – preferably dispenser – sudsy action/alkali content removes germs
Warm water – creates better lather than cold Friction – rubs off pathogens from skin
surface Clean all surface area of hands Point fingertips downward Dry paper towels to turn faucet on and off –
pathogens can travel through wet paper towel
Clean nails – brush or rubbing against palms
Soap
Used as a cleansing agent Aid in removal of germs through
sudsing and alkali content Pathogens trapped in soap suds and
rinsed away Liquid soap better than bar soap
Warm water
Less damage to skin than hot water Increases lather of soap better than
cold water
Friction
Must use friction - rubs off pathogens from surface of skin
Rub hands together using friction for approximately 20 seconds.
Clean all Surfaces
Clean all surfaces of hands – including palms, back and tops of hands, between fingers.
Nails
Nails must be cleaned with an orange/cuticle stick, brush, or rubbing the nails against the palm of the opposite hand.
Nails must be kept short to prevent scratching the skin, injuring patients, breaking through gloves.
Point Fingertips Downward
Keep fingertips pointed downward. Downward direction prevents water from going up forearms and then running down to contaminate clean hands.
Turn faucet off with dry paper towels
Dry paper towels must be used to turn faucet off. This prevents the contamination of the hands from pathogens on the faucet. Pathogens can travel easier through a wet paper towel than a dry paper towel.
Application:
Head to sinks to practice!
Standard Precautions
Standard Precautions – rules developed by the CDC to prevent the spread of infection
Every body fluid and every patient is considered a potential source of infection
OSHA developed:Bloodborne Pathogen StandardNeedlestick Safety Act
Application:
Read pg 377 Bloodborne Pathogen Standard
What are the 3 pathogens of major concern to healthcare workers?
Who created the Bloodborne Pathogen Standard?
What is PPE and what is an employer’s responsibility regarding PPE?
Application:
Read pg 377 Needlestick Safety Act Who developed the Needlestick
Safety Act? Why was this act passed? List 4 requirements of employers
regarding the Needlestick Safety Act. Give an example of each.
Standard Precautions
Basic rules of standard precautions: Hand hygiene Gloves Gowns Masks and eye protection Sharps Spills and splashes Resuscitation devices
Cont’d
Waste and linen disposal injuries
PPE
PPE – Personal Protective Equipment
Donning PPE
Gown Mask Goggles Gloves
Removing PPE
Gloves Gown Eyewear Mask
Application:
Read pgs 385—387 Sterilizing with Autoclave
Read pgs. 392-393 Using Chemicals for Disinfecting
Read pgs. 394-395 Cleaning with an Ultrasonic Cleaner
Describe each method.
Sterile Technique
Sterile = free from all pathogens Contaminated = pathogens present Sterile field – never reach across a sterile
field
What is the difference between clean and sterile?
Create a double bubble map comparing and contrasting using an autoclave vs. disinfecting with chemicals.
Transmission-Based Isolation Procedures Communicable disease – a disease
which is caused by a pathogen which can easily be transmitted to others.
Read pg 408 What is the difference between a
pandemic and an epidemic
Epidemic – occurs when communicable disease spreads rapidly from person to person and affects a large number of people at the same time
Pandemic – exists when the outbreak of disease occurs over a wide geographical area and a effect a large portion of the population
Transmission-Based Isolation Precautions Methods or techniques of caring for
people with communicable diseases Ex: TB, whooping cough, wound
infections Standard Precautions are used on all
patients Transmission –Based Isolation
techniques are used to provide extra protection against specific diseases.
The type of transmission –based isolation precaution used depends on the diseaes
Application:
Read pgs.409-413 Create a double bubble map which
compares and contrasts 2 types of transmission-based isolation precautions
Airborne Precautions
Patients who are infected with pathogens transmitted by airborne droplet nuclei
Ex: measles (rubella), varicella (chicken pox), TB
Precautions: door kept closed, healthcare providers and visitors wear HEPA mask
Pt wears surgical mask if leaves room
Droplet Precautions
Pt infected with pathogens transmitted by large-particle droplets expelled during coughing, sneezing, talking,etc
Ex: flu (influenza), meningitis, pneumonia
Private room Masks
Contact Precautions
Pt infected with pathogens that can be easily transmitted by either direct or indirect contact
Ex: gastrointestinal, respiratory, skin or wound infections
Private room, gloves, gown, linens changed daily
Reverse Isolation
Methods used to protect certain patients from microorganisms
Used mainly for immunocompromised pts
Ex: transplant pts, chemotherapy , severely burned pts, weak immune system
Place in room that has been cleaned and disinfected, gloves, gown, mask, frequent disinfecting of room, special filters may be used to purify air.
Group Work to Demonstrate Working in a Hospital Isolation Unit
Divide into 7 groups
Reader Recorder Reporter
Group 1: Donning Isolation Garments
Group 2: Transfer food Group 3: dispose of leftover food Group 4: transfer of soiled linens Group 5: transfer trash Group 6: transfer equipment Group 7: Removing Isolation
Garments