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Over the years 2008�C2011 at ITM, we observed false-positive test lines for both a PfHRP2-detecting and a Pf-pLDH-detecting three-band RDT product in 0.4% of samples when using PCR as the reference method (results not published). There was an additional 0.8% of false-positive PfHRP2 lines, which may in part be explained by PfHRP2 persistence after a past P.?falciparum infection: PfHRP2 can persist in the blood for up to several weeks after successful treatment due to a low clearance [13]. False-positive RDT results in patients with no recent history of malaria have been observed in patients with other infections (e.g. dengue, hepatitis C, [http://en.wikipedia.org/wiki/Transducin Transducin] toxoplasmosis, tuberculosis and schistosomiasis) or with circulating immunological factors (e.g. rheumatoid factor and anti-nuclear antibodies) [7, 25, 26]. Rapid diagnostic tests are not designed to give an indication of parasite density. A statistically positive correlation between RDT line intensity and parasite density has been observed but there was overlap between the line intensity categories (faint, weak, medium and strong) [6, 7, 9]. For example, although strong PfHRP2 line intensities mainly occurred at parasite densities >100/��L, they were also present at lower parasite densities as well as in samples with pure gametocytemia [6, 9]. The presence of a single PfHRP2 test line was almost exclusively [http://www.selleckchem.com/products/gsk126.html selleck products] found at low ([http://www.selleckchem.com/products/Staurosporine.html Staurosporine molecular weight] traced to inadequacies in the RDTs' instructions for use and further study revealed multiple shortcomings in packaging, labelling and instructions of many RDT products, including CE-labelled ones [3, 31]. Rapid diagnostic tests are not foolproof and errors may occur. Apart from the lower sensitivity at low parasite densities discussed above, there is the prozone effect: an absent or faint test line due to an excess of antigens blocking the binding sites of both detection and capture antibodies, hindering binding of the antigen-detection antibody-conjugate complex to the capture antibody, with failure of signal generation. PfHRP2-detecting but not Pf-pLDH-detecting test lines are affected by the prozone effect [32, 33].