Abstract:
Background: Plasmodium falciparum (P. falciparum) histidine-rich protein2 (HRP2) and
pan-Plasmodium lactate dehydrogenase (pLDH)-based rapid malaria diagnostic tests (RDTs)
play a critical role in malaria control in endemic countries. NxTek
TM Eliminate Malaria
PfAgis newly developed HRP2-based highly sensitive malaria RDT. However, hardly any
data on its field diagnostic performances are not available in the Jimma zone in south-western
Ethiopia.
Objective: To evaluate the diagnostic performance of the NxTek
TM Eliminate Malaria
PfAgagainst quantitative PCR (qPCR) for the detection of asymptomatic P. falciparum
malaria infection amongschoolchildren from September –December2021.
Methods:A school-based cross-sectional study was conducted from September to December
2021on 994 healthy school children (aged 5 to 15 years) using the multi-stage sampling
technique. Finger-pricked blood samples were collected for microscopy, NxTek
TM Eliminate
Malaria PfAg, conventional RDT (Co-RDT), SD Bioline, and QuantStudio Multiplex PCR.
Giemsa-stained blood smears were examined microscopically. Dry blood spots (DBS) were
collected for qPCR assay.
Results: The overall prevalence of asymptomatic malaria was 5%. The prevalence of P.
falciparum was 4.5% by qPCR, 2.2% by NxTek
TM Eliminate Malaria PfAg/Co-RDT, and
1.5% by microscope. Compared to qPCR, the sensitivity of NxTek
TM Eliminate Malaria
PfAgwas 44% and the specificity 100%. PPV and NPV were 100% and 97.43%, respectively.
The accuracy of the test was 97.5%. The kappa value was reported as 0.62, indicating
substantial agreement between the methods. Compared to the microscope, the sensitivity of
the NxTek
TM Eliminate Malaria PfAgwas 68.2% while the specificity was 100%. PPV and
NPV were 100% and 99.5%, respectively. The accuracy of the test was 99.5%. The kappa
value of 0.81 shows perfect agreement between the test methods.
Conclusion: The results presented here suggest that NxTek
TM Eliminate Malaria PfAghas a
satisfactory agreement with qPCR and is a more sensitive tool than the microscope in
asymptomatic children and could represent an alternative diagnostic tool for malariacontrol
programs.
