how to detect a virus Flashcards
1
Q
discuss diagnostic tests for SARS-CoV-2
A
- reverse transcriptase-qPCR tests to detect viral sequences
- ELISA for viral antibody & antigen detection
- serum viral neutralisation assays for antibodies
- genetic & proteomic sequences of the virus
2
Q
describe RT-qPCR is used to test for SARS-CoV-2
A
detect viral sequences such as:
- detects N gene (nucleocapsid)
- detects S gene (spike)
- O gene (Orf1a/b)
3
Q
explain what a positive SARS-CoV-2 result tells you
A
- the swab contained viral genetic material
- the individual tested is/was infected
- the individual tested might still be infectious
4
Q
explain what a negative SARS-CoV-2 result tells you
A
- the swab didn’t contain viral RNA material
5
Q
how to do lateral flow tests
A
- use antibodies to detect analytes
- lateral flow antigen tests detect proteins
- LFT are used to test for exposure of antibodies specific to the antigens
6
Q
explain what a positive SARS-CoV-2 result tells you
A
- the test contained viral antigen
- the individual tested is/was infected
- the individual tested might still be infectious
7
Q
explain what a negative SARS-CoV-2 result tells you
A
- the test didn’t contain viral RNA material
8
Q
what does a positive control tell you
A
- if your assay can detect positive samples
- if negative results are likely to be true
9
Q
what does a negative control tell you
A
- should not show any change during the experiment
- used to control unknown variables
10
Q
discuss new techniques for detection of viral pathogens
A
- loop mediated isothermal amplification (LAMP)
- nucleic acid detection with CRISPR nucleases
- various sequencing based approaches
11
Q
LAMP
A
- isothermal: constant temp
- unlike PCR or qPCR, has automation
- reverse transcription-LAMP assay has a rt step
- specially designed primers
- uses a special DNA polymerase
- makes dumbell structures to see exponential DNA amplification
