Rapid Diagnostic Tests for Malaria
Malaria rapid diagnostic tests (RDTs) are increasingly used as a tool for the diagnosis of malaria, both in endemic and in non-endemic settings. Microscopy remains the cornerstone of diagnosis, but RDTs to detect Plasmodium-specific antigens (proteins) in whole blood of infected people have emerged as an attractive alternative where high quality microscopy is not available.
RDTs detect Plasmodium parasites in blood by antibody-antigen reactions on a nitrocellulose strip, which become visible as cherry-red lines. Different formats exist: two-band RDTs are mostly designed to detect Plasmodium falciparum. They display a control line and a test line, which targets either histidine-rich protein-2 (HRP-2) or P. falciparum-specific parasite lactate dehydrogenase (Pf-pLDH). Three- and four-band RDTs display a control line and two or three test lines, one targeting a P. falciparum specific antigen, a second line targeting antigens common to the four species, such as pan-Plasmodium-specific lactate parasite dehydrogenase (pan-pLDH) or aldolase, and in case of the four band RDTs, a third line which targets Plasmodium vivax-specific pLDH (Pv-pLDH).
EQA scheme run by UKNEQAS Parasitology is comprised of 2 distributions per annum with 2 samples included in each distribution. 250 microlitre of positive or negative blood samples are sent to participants of the scheme.