Malaria infection prevalence and diagnostic performance of the Abbott Bioline Malaria Ag P.f/Pan rapid test in rural populations of Central Cameroon

Abstract

In Cameroon, the management of uncomplicated malaria cases in the communities and in low-resource health facilities rely on the use of reliable rapid diagnostic tests (RDTs). This work was undertaken to determine the trend in human malaria infection in rural settings of Central Cameroon and assess the diagnostic performance of Abbott Bioline Malaria Ag P.f/Pan RDT recommended by the National Malaria Control Programme (NMCP). Cross-sectional surveys were conducted in March 2022 and May 2024. Plasmodium infection was detected using RDT and microscopy techniques, and with real-time PCR for validation of discordant results. Sensitivity (Se), specificity (Sp), positive and negative predictive values, positive and negative likelihood ratios (LR + and LR-), accuracy and agreement were calculated to assess the performance of the RDT. Plasmodium infection prevalence was 64.9% and 71.7% by microscopy and RDT, respectively, Plasmodium falciparum being the predominant species (microscopy:97.48%). With microscopy as reference, the RDT showed high sensitivity (Se:93.37%; CI:91.15%-95.77%) and low specificity (Sp: 68.50%; CI:62.40%-74.17%) for the detection of P. falciparum infection. The positive and negative predictive values were respectively 84.43% (CI:81.01%-87.46%) and 85.71% (CI:80.13%-90.22%). The RDT showed a small positive likelihood ratio (LR + = 2.96; CI:2.47-3.5734), a good negative likelihood ratio (LR-=0.09; CI:0.06-0.13) and moderate agreement (k = 0.652; CI:0.593-0.710; P < 0.001) with microscopy. The RDT showed higher sensitivity (81.48% vs. 48.14%), accuracy (0.75 and vs. 0.50), and agreement (AC1 = 0.715 vs. 0.371) than microscopy. The Abbott Bioline Malaria Ag P.f/Pan RDT demonstrated a high level of agreement with the most sensitive qPCR technique compared to microscopy. These findings further support its use as a reliable malaria diagnostic tool in the highly endemic setting of Central Cameroon.