Evaluation of four rapid diagnostic tests for the diagnosis of Plasmodium vivax in Korea

Summary objective To evaluate 4 rapid malaria diagnostic kits (RDTs) in Korea: OptiMAL test, SD BIOLINEMalaria Ag P.f⁄Pan test, Humasis Malaria P.f⁄Pan antigen test and CareStart Malaria Pf⁄PvCombo test.methods Hundred malaria patients with Plasmodium vivax (P. vivax) and 100 healthy volunteerswere recruited. The results from earlier four RDTs were compared with the reference standard, theGiemsa-stained traditional microscopic diagnosis.results Compared with the reference standard, the sensitivity and specificity for Plasmodium vivaxwere 92.7 and 100% for SD BIOLINE Malaria Ag P.f⁄Pan; and 94.6% and 100% for OptiMAL; 95.5%and 100% for both Humasis Malaria P.f⁄Pan antigen test and CareStart Malaria Pf⁄Pv Combo test.conclusion The performances of all four malaria RDT kits were acceptable, although HumasisMalaria P.f⁄Pan antigen test and CareStartTM Malaria Pf⁄Pv Combo test gave superior performanceswith ROK isolates.keywords Plasmodium vivax, OptiMAL, CareStart, sensitivity, specificityIntroductionPlasmodium vivax (P. vivax) malaria continues to be amajor health problem in the Republic of Korea (ROK),especially near the Demilitarized Zone. Countless effortsagainst malaria have been proposed and launched over thepast three decades. While the spread of P. vivax wasbrought down to manageable levels, malaria transmissionbecame worse in certain locations such as Paju andChulwon. Thus, the overall incidence and prevalence ofmalaria increased (Lim et al. 1999; Lee et al. 2002). Untilrecently, the identification of malarial species dependedupon an expert reading of a Giemsa-stained thin and thickperipheral blood smear. This had many disadvantages, asrelatively few properly trained staff have access to therequired equipment, and rapid and accurate diagnosis ofmalaria are essential to reduce its morbidity and mortality.In 1996, WHO emphasised the urgent need for thedevelopment of simple and cost-effective malaria diagnos-tic tests to overcome the limitations of the clinical diagnosisand accessible light microscopy (WHO Informal Consul-tation on Recent Advances in Diagnostic Techniques andVaccines for Malaria 1996).OptiMAL (DiaMed, Cressier, Switzerland) was the firstrapid malaria test using the immunochromatographymethod (Makler et al. 1998). In the meantime, numerousRDT brands and different products were developed andevaluated for their specificity and sensitivity under differentepidemiological settings and locations, including ROK, asan alternative method to the malaria diagnosis by bloodsmears (Iqbal et al. 2002; Kim et al. 2008; Ashton et al.2010; Cho et al. 2011). WHO and Foundation for Inno-vative New Diagnostics (FIND) evaluated 70 test kits from26 manufacturers (WHO 2008, 2009). The WHO⁄FINDproduct testing of malaria RDTs (WHO 2009, 2010a,b)was the most comprehensive assessment of malaria RDTson the market. However, some field test results showeddiscrepancies to the WHO reports (Ashton et al. 2010).Moreover, some studies indicated that the sensitivity andspecificity of aldolase-based RDT, Binax Now malaria,were not appropriate for the detection of P. vivax in ROK(Cho et al. 2001, 2011).