| Diagnostic methods | Pros and cons |
| Parasitological diagnosis | |
| Microfilariae may be found in the peripheral blood between 10 p.m. and 2 a.m. for most species and subspecies. Microfilariae can be differentiated after staining of thick haemolysed blood films or after concentration of citrated blood (e.g. on polycarbonate membranes). Membrane filtration of 1 or 2 ml blood is the standard diagnostic procedure! | - Sensitivity of parasitological method is limited since in pre-patent, in light and post-patent infections, no microfilariae are detectable
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| Molecular diagnosis | |
| PCR followed by RFLP analysis may be used to differentiate filariae of different species in co-endemic areas (e.g. infective larvae in the vector). A recent multiplex PCR method allowed the simultaneous detection of Brugia and Wuchereria in blood and mosquito samples. | - Molecular diagnosis is valuable for epidemiological studies
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| Antigen detection | |
| For Wuchereria bancrofti infections, several immunochromatographic rapid diagnostic tests detecting circulating filarial antigens in whole blood are commercially available. However, they do not detect infections with Brugia spp. | - High sensitivity (>95%); however restricted to Wuchereria bancrofti infections
- Excellent specificity
- Easy test procedure
- No need to take night blood!
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| Antibody detection | |
Many home-made serological tests have been developed for which specificity is the main problem. Extensive cross-reactivity with other filarial infections and strongyloidiasis.
High antibody levels in tropical pulmonary eosinophilia. | - Serological tests have high sensitivities but poor specificities
- No correlation with worm load
- No need to take night blood
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