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Background As the global public-health objectives for malaria evolve from malaria control towards malaria elimination, there is increasing interest in the significance of asymptomatic infections and the optimal diagnostic test to identify them. Method We conducted a cross-sectional study of asymptomatic individuals (N = 562) to determine the epidemiological characteristics associated with asymptomatic malaria. Participants were tested by rapid diagnostic tests (CareStart, Standard Diagnostics [SD] Bioline, and Alere ultrasensitive RDT [uRDT]), loop-mediated isothermal amplification (LAMP), and quantitative reverse transcription polymerase chain reaction (qRT-PCR) to determine malaria positivity. Hemoglobin values were recorded, and anemia was defined as a binary variable, according to World Health Organization guidelines. Results Compared to reference qRT-PCR, LAMP had the highest sensitivity (92.6%, 95% confidence interval [CI] 86.4–96.5), followed by uRDT Alere Malaria (33.9%, 95% CI 25.5–43.1), CareStart Malaria (14.1%, 95% CI 8.4–21.5), microscopy (5.0%, 95% CI 1.8–10.5), and SD Bioline (5.0%, 95% CI 1.8–10.5). For Plasmodium falciparum specimens only, the sensitivity for uRDT Alere Malaria was 50.0% (95% CI 38.8–61.3) and SD Bioline was 7.3% (95% CI 2.7–15.3). Based on multivariate regression analysis with qRT-PCR as the gold standard, for every 3.2% increase in the prevalence of asymptomatic malaria, hemoglobin decreased by 1 gram per deciliter (prevalence ratio 0.968, 95% CI 0.940–0.997; P =.032). Deletions (4.8%) in hrp2 were noted. Conclusions While uRDT Alere Malaria has superior sensitivity to rapid diagnostic tests and microscopy in detecting asymptomatic malaria, LAMP is superior still. Ultrasensitive diagnostics provide the accurate prevalence estimates of asymptomatic malaria required for elimination. [ABSTRACT FROM AUTHOR]

Mutations in the Plasmodium falciparum K13-propeller domain have recently been shown to be important determinants of artemisinin resistance in Southeast Asia. This study investigated the prevalence of K13-propeller polymorphisms across sub-Saharan Africa. A total of 1212 P. falciparum samples collected from 12 countries were sequenced. None of the K13-propeller mutations previously reported in Southeast Asia were found, but 22 unique mutations were detected, of which 7 were nonsynonymous. Allele frequencies ranged between 1% and 3%. Three mutations were observed in >1 country, and the A578S was present in parasites from 5 countries. This study provides the baseline prevalence of K13- propeller mutations in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]