RDT test: formats of tests

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RDT Test Formats

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' Single test-band RDT tests This test format usually uses a species specific antibody recognising P.falciparum (the HRP2 antigen or Pf-LDH). These tests detect infection by P.falciparum only. The format offers particular advantages: Simple interpretation lower production cost Stability (of HRP2) for storage and transport Use: The single band test detecting only P.falciparum is very useful in Africa, since in many areas infections with this species account for more than 95% of malarial infection. The test is very useful in more remote areas where technical expertise in microscopy and interprtation is often less available. However, this is at the cost missing other species. For this reason their use is limited to certain regions (particularly sub-Saharan Africa) where P.falciparum is dominant (>95% of infections). Multi-band RDT tests These use two (or occasionally more) test bands together with a control band. Most often one band is a species-specific antibody that identifies the dominant (or most important) species for the selected region (generally P.falciparum but in saome areas P.vivax). The second band is most often a pan-malaria antibody. The format offers advantages: It provides the capability to detect infection with a second species The pan malaria antibody can provide a "back up" if the first band fails However, the limitations of this test form must be understood by users. In particular the poor sensitivity of pan-malarial antibodies for some species (P.ovale or P.malariae). In some circumstances RDT tests have been adapted to overcome particular problems, some are described here: Emerging strategies and options