Lists the categories of micro-organism that cause infection.
List the common sterile sites in the body
- CSF(cerebro-spinal fluid)
List the non-sterile sites in the body
Urethra (a tube that connects the urinary bladder to the urinary meatus for the removal of urine from the body.)
Outline the role of microscopy in bacterial infection.
Light microscopy (x1000 magnification)
- Unstained - to see pus cells (e.g.urine, CSF)
- to see parasites (faeces)
- Gram stain - to see bacteria and yeasts/fungi
- Viruses not visible in light microscope
Explain the difference between sterile and non sterile sites.
- Sterile sites should contain no micro-organisms
- Non-sterile sites may contain commensal microbes that may not harm the body, but still show up in microscopy or cultures.
Outline the methods of detecting viruses
- Molecular methods-real time PCR
Serology to determine immunity (antibodies in serum)
- Used rarely: Electron microscopy/ Cell or tissue culture - inoculate a “cell line"
Outline the diagnostic principles in parasitology
- Microscopy of different stages: parasites, cysts and ova in faeces.
Blood films for malaria
- Culture rarely possible
Serology sometimes useful
Describe basic infection control measures
- Wash hands before touching patient
- Wash hands or apply alcohol gel between patients
- Swab stethoscope between patients
- Patients isolated in single room (“barrier nursed” or source isolation) have extra precautions:
- Wash hands, wear plastic apron
- On leaving, dispose of apron, wash hands
List the common specimen types collected for culture.
- Urinary tract infection - mid-stream urine (MSU)
- Chest infection – sputum
- Tonsillitis/pharyngitis – throat swab
- Wound or site of infection - swab or pus (swabs are sent in bacterial transport medium)
- Diarrhoea - faeces
- Bacteraemia - blood culture
- Meningitis - cerebro-spinal fluid (CSF)
Feutures of gram stain & Microscopy
- Not sensitive
- Can’t usually identify particular species
Features of cell culture
- Culture conditions suitable for the expected species
4 Healthcare Acquired Infection