Disinfectants and Sterilisation Flashcards
What is the difference between biosecurity and infection control
Biosecurity = stopping infection coming onto site
Infection control = process to reduce risk of infection on site
Name the 4 levels of cleaning and explain them
- Physical cleaning - removing material or contamination
- Sanitation - Application of chemicals to reduce contamination
- Disinfection - using products to kill pathogens +/- spores
- Sterilisation - inactivation of pathogens and spores
List organisms in order from highly susceptible to highly resistant to disinfection
Gram -ve, fungal spores, prions, mycobacterium, gram +ve, mycoplasmas, enveloped viruses, non-enveloped viruses
Mycoplasmas
Gram -ve bacteria
Enveloped viruses
Gram +ve bacteria
Fungal spores
Non-enveloped viruses
Mycobacterium
Prions
Name some considerations when an infectious animal is coming into practice
Hygiene protocols - cleaning, PPE, personal safety, bedding
Waste Management - correct route, sharps etc.
Name 5 ways to prevent entry of Streptococcus equi (strangles) to a yard
- Quarantine and screening of new arrivals
- Disinfecting at risk fomites
- Education of handlers
- Detection and treatment of carriers
- Biosecurity
Give infection control examples for Streptococcus equi
Route of infection - close contact and aerosols
Cleaning followed by disinfection of common areas
Household bleach is effective at disinfection
After quarantining, rest pasture for several weeks to reduce risk of spread
What actions to take if a horse yard has salmonella infection
Isolate positive cases
Use PPE
When doing rounds of the animals => positive cases last, use separate equipment
Manage waste correctly
Clean before disinfection - organic material reduces the effectiveness of disinfectants
Reduce traffic to the yard - risk of spread
Name some approaches to the management of a parvovirus case
Vaccination/ biosecurity prior to vaccination
Need good biosecurity on admission of the case
Infection control:
- Barrier controls (isolation kennel?)
- PPE management and hygiene
- Use hypochlorite (household bleach) to disinfect - needs 1 hour contact time
What is pasteurisation and what is it used for in the food industry
Is the passing of heat over an item
More commonly used to kill microorganisms in the food industry
What type of bacteria is pasteurisation not effective against
Spore forming bacteria
Name the 3 types of autoclaves
- Vertical pressure cooker
- Horizontal vertical download displacement autoclave
- Vacuume assisted autoclave
What is the horizontal vertical download displacement autoclave not good for and why
Drapes and gowns
No drying cycle
Name 2 forms of sterilisation
- Chemical sterilisation
- Gas sterilisation
What are the disadvantages of chemical sterilisation
Not very effective
Some liquids can cause problems if placed in the body e.g. left over on instruments
What are the disadvantages of gas sterilisation
Strict COSHH controls - highly toxic
Requires training and specific equipment
Cycles are long - 12-24 hours
All gas must be evacuated before use of the equipment
