How well do RDT tests detect the different malaria species?
The different malaria species are detected with different sensitivity. The table below provides an overall summary of the sensitivity that can be expected for RDT tests when suitable species-specific together with pan-malarial antibodies are used. The table is only a broad summary. Users are advised to understand the characteristics of the test they use including the merits of the antibodies employed in their test (see section below)
P.falciparum1
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| At high parasitaemia expect high sensitivity (90-95%). This declines when parasite levels are lower (45-70%)2
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P.vivax
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| Expect moderate to high sensitivity at high parasitaemia (70-90%). This declines markedly when parasite levels are lower (30-60%)2
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P.ovale & P.malarae
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| Generally sensitivity is poor (approximately half the sensitivity shown for P.vivax)
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P.knowlesi3
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| Reports suggest variable sensitivity that may depend on test used, RDTs are reported tp detect this species well when parasitaemia is high.
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Notes:
1 HRP2 mutation mean that in some geographical areas the diagnostic sensitivity may be significantly lower for HRP2-based tests (see below)
2 Low parasite number is considered as (<1000 parasites/μL) a level that may cause symptoms in children or non-immune travellers
3 There have been relatively few studies with this species so caution is required in RDT interpretation
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