Field evaluation of a quantitative, and rapid malaria diagnostic system using a fluorescent Blue-ray optical device

Abstract

We improved a previously developed quantitative malaria diagnostic system based on fluorescent Blue-ray optical device. Here, we first improved the diagnostic system to enable fully automated operation and the field application was evaluated in Kenya. We detected Plasmodium falciparum in blood samples collected from 288 individuals aged 1-16 years using nested polymerase chain reaction (nPCR), rapid diagnostic test (RDT), and automated system. Compared to RDT, the automated system exhibited a higher sensitivity (100%; 95% confidence interval [CI], 93.3-100%) and specificity (92.8%; 95%CI, 88.5-95.8%). The limit of detection was 0.0061%. Linear regression analysis revealed a correlation between the automated system and microscopic examination for detecting parasitemia (adjusted R2 value=0.63, P=1.13x10-12). The automated system exhibited a stable quantification of parasitemia and a higher diagnostic accuracy for parasitemia than RDT. This indicates the potential of this system as a valid alternative to conventional methods used at local health facilities, which lack basic infrastructure.