Diagnostic Tests Flashcards
Describe the features of cultures for pathogen detection
Allows further characterisation of pathogens including antibiotic sensitivity testing
Typically takes a minimum of 2 days
Requires facilities and trained personnel
What tests can be done to detect pathogens via their antigens?
ELISA
Patient-side tests:
- lateral flow devices
- latex agglutination test
Describe the tests used to detect pathogens via genetic material
DNA -> PCR or quantitative PCR (qPCR)
RNA -> reverse transcription -> PCR or qPCR
Name the different inflammatory markers
Fibrinogen
C-reactive protein (CRP) - dog and pig
Serum amyloid A (SAA) - cat, horse, cow
Pig major acute phase protein (pig-MAP)
What are the types of traditional antibody tests?
Agglutination/haemagglutination inhibition
Complement Fixation
What are the different types of ELISA tests?
Indirect
Competition
Describe indirect ELISA antibody testing
Antibodies are added which detect the animal’s antibodies against a pathogen. when they bind the antibody causes a colour change in the substrate
e.g., ELISA for African swine fever virus antibodies
Describe competition ELSIA antibody testing
An antibody is added that competes with the animals own antibodies to bind to the antigen => colour change.
Good for non-species specific pathogens
e.g., ELISA for influenza A virus antibodies
How can active infection be detected using ELISA?
IgM antibody capture (IMAC) ELISA
- antibody coated onto plate that is specific to IgM
- add antigen of interest and see if it has been captured and bound my IgM on the plate
- specific antibody to antigen is added with associated substrate that changes colour when attached to antibody-antigen complex
Give examples of indirect tests for disease
Single intradermal comparative cervical tuberculin test (SICCT)
- type IV hypersensitivity Interferon gamma (IFNγ) test
