Methods of choice | Pros and cons |
For detecting parasitic DNA | |
Polymerase chain reaction (PCR) or nested PCR - Conventional PCR
- Real-time PCR
| - Methods with highest sensitivity and excellent specificity
- Some false-negative results due to inhibitors in sample
- Time-consuming procedure (except real-time PCR)
- Investment in equipment and rather expensive reagents
|
For detecting parasite antigens | |
Immunoassays with mostly specific monoclonal antibodies - Immunoenzyme methods (e.g. ELISA)
- Direct fluorescent antibody tests
- Immunochromatographic assays
(“rapid diagnostic tests”) | - High sensitivity
- Detection of active infections
- Efficient testing of many samples
- False-negatives due to inhibitory host antibodies
|
For detecting antibodies | |
Various indirect immunoassays using labelled anti-human Ig conjugates (e.g. enzyme-immunoassays, indirect fluorescent antibody tests, Western blots and others) | - High sensitivity
- Limitations in specificity (due to crude antigen preparations)
- Limitations in sensitivity (when recombinant antigens or synthetic peptides are used)
- Early diagnosis before patent period (helminth infections)
- Persistence of host antibodies after cure
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