Infection Control Flashcards
microbe/micro-organism
any organism which
is too small to be seen with the naked eye
pathogen
micro-organisms capable of causing disease
infection
pathological process which involves the damaging of body tissues by pathogens, or by the toxic substances produced by these pathogens
5 classifications of pathogenic organisms
virus, bacteria, fungus, protozoa, helminth
virus
much smaller than bacteria and although they may survive outside the body for a time, they can only grow inside body cells
virus treatment
viruses are not susceptible to antibiotics, but there are a few antiviral drugs available which are active against a limited number of viruses
bacteria
minute organisms about one thousandth to five thousandths of a millimetre across
bacteria treatment
susceptible to a greater or lesser extent to antibiotics
pathogenic fungi
can be either moulds or yeasts
ringworm
a mould that causes infections in humans, which can also infect nails
Candida albicans
aka thrush, a common yeast infection
protozoa
microscopic organisms, but are larger than bacteria
non-pathogenic protozoa
freeliving and non pathogenic protozoa include amoebae and paramecium
Giardia lamblia
protozoa, causes enteritis
malaria
protozoa, causes malaria
6 modes of spread of infection
direct contact indirect contact inhalation ingestion faecal-oral inoculation
spread of infection by direct contact
occurs when one person infects the next person by direct contact, i.e. via the skin, mucous membranes, or personal contact with contaminated body secretions/excretions
spread of infection by indirect contact
occurs when an intermediate carrier is involved in the spread of pathogenic microbes from the source of infection to another person
spread of infection by inhalation
occurs when microbes, exhaled or discharged into
the atmosphere by an infected person, are inhaled by and infect another person
spread of infection by ingestion
can occur when organisms capable of infecting
the gastrointestinal tract are ingested
When these organisms are excreted
faecally by an infected person, faecaloral spread may occur.
spread of infection by faecal-oral route
occurs when organisms are excreted by an infected person and make their way to be ingested by another
spread of infection by inoculation
can occur following a ‘sharps’ injury when, for
example, contaminated blood is inoculated into the
blood stream of the victim, thereby causing an infection
fomite
an object which becomes contaminated with infected
organisms, and which subsequently transmits those organisms to another person
vector
an animal, usually an insect, that passively transmits
pathogenic microbes
What is the most common vector in the UK?
the housefly
aerosol
droplet spread of infection causes inhalation spread of infectious disease
3 examples of pathogens spread by aerosol
chickenpox, mumps and measles
What are the most important vehicles of cross-infection?
hands
Define the chain of infection
the process by which infection can be spread from one
susceptible host to another
causative organisms in the chain of infection
to break the chain of infection, the causative organisms must be destroyed or rendered harmless, e.g. the use of disposable equipment, or maintaining effective cleaning and disinfection procedures
reservoir in the chain of infection
a member of staff, a patient, or dust may act as a reservoir, although close attention to cleaning procedures will help reduce this link
portals of entry/exit in the chain of infection
the route by which a pathogen leaves its host is called the portal of exit, and the route by which it enters is called the portal of entry
What are the main portals of entry?
respiratory tract
alimentary canal
skin/mucosa damage
placenta
susceptible host in the chain of infection
the competence of the body’s innate and acquired defence mechanisms will affect whether or not illness occurs and the chain of infection may be broken at this point
host defence mechanisms in chain of infection
non-specific defence mechanisms
specific defence mechanisms: specific immune mechanisms
non-specific defence mechanisms
natural barriers which protect against invasion by pathogens eg skin
specific defence mechanisms
specific immune mechanisms are activated if an organism is able to evade the nonspecific defence system
may not prevent an attack, but will ensure that a memory of the pathogen is retained so that the system can react quickly and destroy the pathogen when it is next encountered
What is the most likely means of transmission of viruses to ambulance staff from patients?
direct percutaneous inoculation of infected blood, by a sharps injury or by blood splashing onto broken skin or mucous membrane
body fluids at risk of containing pathogens
faeces urine vomit sputum blood/blood-stained body fluids vaginal secretions semen bodily tissues CSF/plueral fluid/amniotic fluid/etc
Who is a potential HIV or Hep B/C biohazard?
it is impossible to identify or categorise all those who are seropositive to HIV or Hepatitis B/C, so every
patient is a potential biohazard
Universal Precautions: care of hands
all abrasions, cuts, open lesions etc., must be covered with an impermeable waterproof dressing prior to and during any period of duty
Universal Precautions: personal hygiene
involves close and constant attention to personal hygiene standards, which if maintained will help minimise the risks from cross-infection, and will also impact on the professional and social standing of individuals, as well as promoting a competent and efficient image of the Service
Universal Precautions: handwashing
recognised as the single most effective method for preventing the spread of infection: thorough washing of all surfaces of the hands using soap and running water; rinsed carefully; thorough drying with disposable paper towels
fingernails
care should also be taken to ensure that fingernails are kept short and clean
when to wash hands
-Before and after duty periods
. Before eating and drinking
. After visiting the lavatory
. After carrying out any cleaning procedure
. When hands are visibly dirty
. Before and after performing any invasive procedure
. When gloves are removed
. Before and after each patient contact (and/or after handling their belongings)
. After handling contaminated laundry and waste
gloves and handwashing
the wearing of gloves does not preclude the need for
regular hand-washing because bacterial counts on hands multiply while gloves are being worn (also the possibility of the gloves becoming punctured during use)
when to use alcohol gel
on the occasions when staff are unable to access handwashing facilities on either station or hospital premises, the alcohol hand disinfectant carried on the vehicle must be utilised
when to use alcohol gel
- on the occasions when staff are unable to access handwashing facilities on either station or hospital premises, the alcohol hand disinfectant carried on the vehicle must be utilised
- prior to donning gloves in preparation to perform an invasive procedure
when to wear protective clothing
the choice of protective clothing will depend on the anticipated risk of exposure to blood or body fluids during the particular activity intended, and staff must
use their judgement in determining the likely requirements in each case
PPE provided by LAS to operational staff
Disposable Latex Gloves (3 sizes) Disposable Plastic Aprons Disposable Face Masks Safety Eyewear Pocket Resuscitation Mask
when to don gloves
it is important that gloves are worn for any activity where blood or body fluid may contaminate the hands, just prior to contact with the patient
when to wear apron
whenever contamination of clothing with blood or body fluid is anticipated
when to wear apron
whenever contamination of clothing with blood or body fluid is anticipated, during any cleaning activity, or on any occasion where the front of the uniform is at risk of being soiled
spare uniform
staff must always ensure that they have at least one complete spare uniform
in their station locker, for the occasions when uniform contamination has been
unavoidable
how to discard of used aprons
used aprons that have been contaminated should always be discarded as clinical waste, followed by a thorough washing of the hands
when to use face mask
- for illnesses caused by the more hazardous organisms found in Category 3
- if there is a risk of blood or body fluid being splashed into the mouth
- if the patient is prone to episodes of coughing or sneezing
what PPE for suspected/confirmed pulmonary TB?
face masks, for both staff and pt
Universal Precautions: breathing near pt
attempt to avoid breathing while in close proximity to a patient’s face, in order to help minimise the risk of
cross contamination
when to wear safety eyewear
on any occasion where there is a risk of blood or body fluids coming into contact with the eyes, or when similar risks arise from activities such as vehicle or equipment cleaning
when to wear safety eyewear
on any occasion where there is a risk of blood or body fluids coming into contact with the eyes, or when similar risks arise from activities such as vehicle or equipment cleaning
NOT intended for major chemical
incidents, or where physical impact damage could occur
benefit of pocket mask
minimal risk of exposure to infection
disposability of pocket mask
mask has been designed to be reusable, albeit the one-way valve is strictly for single patient use only, and should be carefully discarded as clinical waste
intended use of pocket mask
to eliminate the need for mouth-to-mouth contact during resuscitation attempts, but should be replaced by the resuscitation pack at the earliest opportunity
extra vehicle cleaning
the key source for the spread of infection emanates from contact with blood and body fluids, so areas where blood or body fluid contamination has occurred will require definitive cleaning and disinfection procedures
How long can airborne pathogens survive outside of a host?
a few seconds
vehicle exterior cleaning
should be maintained in a consistently clean and hygienic condition, vehicle wash facilities
are available on ambulance stations
PPE when cleaning the vehicle exterior
eye protection and disposable aprons, particularly when using the manually operated vehicle wash systems; rubber household gloves, or even the heavy duty ‘debris’ gloves, should be worn in preference to the
normal latex disposable variety
on the occasions where an exterior surface becomes contaminated with blood or body fluids
‘Cleaning System 1’ and ‘Disinfection System 2’ must be utilised to eradicate the potential source of infection, PPE worn throughout, disposed of into a yellow clinical waste bag
interior vehicle cleaning
- frequent and routine cleaning activities for all crew
- each shift, all interior surfaces that become directly contaminated should be cleaned as soon as possible
- regular ‘damp dusting’ throughout the
shift, paying particularly attention to the horizontal surfaces in the ambulance, as well as all fixtures and fittings that are regularly handled - ambulance floor should be mopped clean on a regular basis throughout the shift using hot water and a general detergent
- ‘Cleaning System 1’ as the primary cleaning agent, followed by the use of ‘Disinfection System 2’ if the contamination is likely to contain either blood or body fluids
interior vehicle cleaning
- each shift, all interior surfaces that become directly contaminated should be cleaned as soon as possible
- regular ‘damp dusting’ throughout the
shift, paying particularly attention to the horizontal surfaces in the ambulance, as well as all fixtures and fittings that are regularly handled - ambulance floor should be mopped clean on a regular basis throughout the shift using hot water and a general detergent
- weekly comprehensive clean
- ‘Cleaning System 1’ as the primary cleaning agent, followed by the use of ‘Disinfection System 2’ if the contamination is likely to contain either blood or body fluids
- appropriate items of PPE worn, doors and windows opened
