7 Immunisation and infection control Flashcards
What are our non-specific immune defences?
Unbroken skin.
Mucous membranes of gut + lung.
Acid and enzymes in gut.
Non specific metabolism.
How long do maternal antibodies transferred in the womb protect the baby for?
A year.
What is the definition of an antigen?
Anything that can be bound by an antibody.
Which antibodies are part of the first + second immune response?
1st: IgM.
2nd: IgG.
Which vaccines act through live immunity?
Live, inactivated components, and inactivated toxins.
What constitutes passive immunity?
Vertical transmission and breastfeeding.
Injection of pooled immunoglobulin.
HNIG - pooled plasma.
Specific - tetanus, botulism, hep B, rabies, VZV
Name 4 live vaccines:
MMR.
BCG.
Yellow fever.
VZV.
Name 3 inactivated vaccines:
Pertussis.
Typhoid.
HPV.
Name 2 vaccines made from components of organisms:
Influenza.
Pneumococcal.
Name 2 vaccines made from inactivated toxins:
Diphtheria.
Tetanus.
Advantages and disadvantages of live vaccines:
Single does, strong.
Unstable, revert to virulence, not in immunosepressed, contamination, interference by viruses.
Advantages and disadvantages of inactivated vaccines:
Stable, clear constituents, can’t cause infection.
Several doses needed, local reactions, needs adjutant, shorter lasting.
What are the five key steps in breaking the chain of infection?
Eliminate pathogenic organism. Remove source/reservoir. Minimise transmission. Eliminate exit and entry. Reduce susceptibility.
What 4 steps are taken to eliminate pathogenic organisms?
Environmental cleaning: H2O2.
Equipment decontamination: sterilise + disinfect
Antisepsis: skin prep, MRSA decon
Antibiotic prophylaxis
What two steps are taken to remove the source/resevoir of infections?
Hand hygiene.
Environmental cleaning and decontamination.
Which 5 steps are taken to minimise transmission of infections organisms?
Hand hygiene. PPE. Equipment decontamination. Source isolation Disposable equipment use.
Which 5 steps are taken to eliminate entry of organisms?
Antisepsis. Asepsis. Air handling (+ve kPa, laminar flow). Sharps management. Patient management (invasive devices).
What 2 steps are taken to reduce susceptibility to infection?
Antibiotic stewardship.
Immunisation.
Define sterilisation. 4 methods.
Complete killing or removal of all types of micro-organisms.
Heat, chemical, filtration, ionising radiation.
How is sterilisation by heat performed?
Moist: autoclave - steam, high kPa.
Dry: oven.
Define disinfection.
Removal or destruction of sufficient numbers of potential harmful micro-organisms to make an item safe to use.
Define antisepsis.
Disinfection when applied to living tissue or damaged skin.
Chemical disinfection is largely limited to:
Environmental decontamination (spills, surfaces).
Antisepsis.
Heat-sensitive items.
What infection control method is used for surgical instrument reprocessing?
Sterilisation by moist heat.
What infection control method is used for flexible endoscopes?
High level disinfection by chemical methods.
What infection control method is used for syringe needles?
Sterilisation: gamma irradiation pre use and disposal afterwards.
What infection control method is used for central venous catheter site?
Antisepsis: 2% chlohexidine in 70% isopropyl alcohol.
What infection control method is used for a surgeons hands?
Washing with surgical scrub.
