Advanced Microbiology - Prevention and Control Flashcards
Chain of infection (6)
- can intervene at each step to prevent spread of infection
Pathogen –> reservoir –> exit –> mode of transmission –> entrance –> host –> pathogen spread
Decontamination includes? (in order of severity)
Cleaning, Disinfect and Sterilisation
Decontamination VS anti-sepsis
BOTH to eliminate pathogen
BUT anti-sepsis is when applied to living tissue
Disinfectant VS sterilization
Disinfecting = removal of sufficient number of potentially harmful organisms eg. surfaces and spills
Sterilization = complete killing of all types of micro-organism particularly C. diff vegetative spores.
Methods of Sterilisation (4)
Heat has 2 types
Heat
- Moist = in autoclave high pressure steam and temp
- Dry = oven
Chemical - gas (H2O2) or liquid
Filtration
Ionising radiation (single use disposable equipment)
Methods to ‘remove the reservoir’
Hand washing and decontamination
When to hand wash? + most important
By either alcohol gel or soap and water
Before contact *Before aseptic task *after bodily fluid exposure after patient contact After contact with patient surroundings
Methods to minimize transmission (4)
Hand washing and PPE (personal protection equipment)
Decontamination
Sterilisation of equipment OR single use
Source protection and isolation
Methods to eliminate exit and entrance?
treatments
Methods to protect the susceptible host?
Vaccinations
Which decontamination method to use is based on?
Risk of infection Physical properties of equipment being used Chemical properties of cleaning product Physical properties of cleaning product harmful effects of cleaning product
How should we clean: items that enter sterile parts of the body or break the skin?
STERILISE
how should we clean: items that come in contact with mucous membranes or bodily fluids
DISINFECT
how should we clean: items that come in contact with unbroken skin
CLEAN
Diseases with vaccines against them (17)
Polio Mumps Diphtheria Tetanus Rubella Measles Acute meningitis (ACWY) Meningococcal Septiceamia Whooping cough HPV Hep A, B and C Typhoid TB (BCG injection) Anthrax Yellow Fever Varicella Zoster Flu
Passive immunity? two types
Last a few weeks
Vertical transmission of Antibodies from mother to child
HNIG - plasma injections with specific antibodies
Active Immunity? two types
Lasts a long time
Infection - body creates the antibodies + plasma cells = memory
Vaccination - creates antibodies without disease occuring
Examples of Live vaccinations? (4)
MRR, BGC, Varicella, yellow fever
Attenuated pathogen? - what does it mean
been weakened so still invade the host but don’t cause the disease (virulence reduced)
Inactivated Vaccinations examples? (8)
Pertussis Influenza Rabies Hep A Typhoid IPV Diphtheria HIB - heamophillus influenza type B
Suspensions? inactivated vaccines?
whole intact dead organism - with antigens which stimulate antibody production
Acellular sub unit vaccinations?
Part of the dead organism (just the antigens)
Susceptible population?
any one not immune to particular pathogen
- not encountered the infection
- not had the vaccination (counter indicated for them)
- unable to amount an immune response (immunosupressed)
Active VS inactive vaccination (2 for and 2 against for both)
Live = single does sufficient, strong immune response
BUT counter indicated for immunosupressed and could turn virulent
Inactive = Several doses, shorter acting, local reaction
BUT Stable constituents and not able to cause an infection
