Performance of Malaria Rapid Diagnostic Test in Asymptomatic Malaria Cases in Stable Transmission Area in Kisantu, Democratic Republic of Congo

Abstract

<i>Background</i>: Democratic Republic of Congo has shifted from pan test to mono-specific malaria RDT tests. A new Histidine rich protein 2 (HRP2)-based Rapid Diagnostic Tests for malaria diagnosis was then implemented. <i>Objective</i>: This study evaluated the performances of this new diagnostic tool compared to the thick smear as the gold standard. <i>Method</i>: The study was conducted in Kisantu Health zone in the Democratic Republic of the Congo (DRC) where malaria is known as endemic disease. Asymptomatic children aged between 0 and 10 years were included in the study. Malaria tests such as Rapid Diagnostic test (RDT) and blood smear were perform in all enrolled children. Blood smear was considered as a reference test. In the performance analysis, only thick positive smears confirmed as <i>Pf</i> by thin smear were considered positive in calculation. The sensitivity, specificity and positive and negative predictive values of CareStart Malaria <i>Pf</i> (HRP-2) RTD Ag compared to the thick smear. <i>Result</i>: The prevalence of malaria infection was 78.3% and 14.7% using rapid diagnostic test and thick blood smear, respectively. Considering the gold standard, proportion of false positives was 77.5%. The Sensitivity was 83.1% (CI95%: 72.4-94.9) and specificity was 22.5% (CI95%: 20.2-25.0). The Positive Predictive Value (PPV) was 15.2% and Negative Predictive Value (NPV) was 88.9%. It appears that the HRP2-based test presently used in the Democratic Republic of Congo over estimates malaria infections. <i>Conclusion</i>: CareStart Malaria Pf (HRP-2) RTD Ag, currently in use in the DRC detects a very high proportion of false positives. Those children falsely positive were subject to be treated unnecessarily. Therefore, there is need of adapting the choice of RDT for malaria policy accordingly.