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Introduction: The World Health Organization recommends regular monitoring of the efficacy of nationally recommended antimalarial drugs. We present the results of studies on the efficacy of recommended antimalarials and molecular markers of artemisinin and partner resistance in Afghanistan, Pakistan, Somalia, Sudan and Yemen. Methods: Single‐arm prospective studies were conducted to evaluate the efficacy of artesunate‐sulfadoxine‐pyrimethamine (ASSP) in Afghanistan and Pakistan, artemether‐lumefantrine (AL) in all countries, or dihydroartemisinin‐piperaquine (DP) in Sudan for the treatment of Plasmodium falciparum. The efficacy of chloroquine (CQ) and AL for the treatment of Plasmodium vivax was evaluated in Afghanistan and Somalia, respectively. Patients were treated and monitored for 28 (CQ, ASSP and AL) or 42 (DP) days. Polymerase chain reaction (PCR)‐corrected cure rate and parasite positivity rate at Day 3 were estimated. Mutations in the P. falciparum kelch 13 (Pfk13) gene and amplifications of plasmepsin (Pfpm2) and multidrug resistance‐1 (Pfmdr‐1) genes were also studied. Results: A total of 1680 (249 for ASSP, 1079 for AL and 352 for DP) falciparum cases were successfully assessed. A PCR‐adjusted ASSP cure rate of 100% was observed in Afghanistan and Pakistan. For AL, the cure rate was 100% in all but four sites in Sudan, where cure rates ranged from 92.1% to 98.8%. All but one patient were parasite‐free at Day 3. For P. vivax, cure rates were 98.2% for CQ and 100% for AL. None of the samples from Afghanistan, Pakistan and Yemen had a Pfk13 mutation known to be associated with artemisinin resistance. In Sudan, the validated Pfk13 R622I mutation accounted for 53.8% (14/26) of the detected non‐synonymous Pfk13 mutations, most of which were repeatedly detected in Gadaref. A prevalence of 2.7% and 9.3% of Pfmdr1 amplification was observed in Pakistan and Yemen, respectively. Conclusion: High efficacy of ASSP, AL and DP in the treatment of uncomplicated falciparum infection and of CQ and AL in the treatment of P. vivax was observed in the respective countries. The repeated detection of a relatively high rate of Pfk13 R622I mutation in Sudan underscores the need for close monitoring of the efficacy of recommended ACTs, parasite clearance rates and Pfk13 mutations in Sudan and beyond. Registration numbers of the trials: ACTRN12622000944730 and ACTRN12622000873729 for Afghanistan, ACTRN12620000426987 and ACTRN12617001025325 for Pakistan, ACTRN12618001224213 for Somalia, ACTRN12617000276358, ACTRN12622000930785 and ACTRN12618001800213 for Sudan and ACTRN12617000283370 for Yemen. [ABSTRACT FROM AUTHOR]

We developed a new sensor based on spinel zinc ferrite nanoparticles (ZnFe2O4) and reduced graphene oxide (RGO) decorated electrode, or ZnFe2O4/RGO nanocomposite, which characterized with various techniques, including Raman spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed admirable crystallinity and large surface area for the proposed electrode. Moreover, a screen printed electrode (SPE) was modified with ZnFe2O4/RGO nanocomposite (ZnFe2O4/RGO/SPE) for detection of Sudan I sensitively and selectively. Sudan I electrochemical responses appeared in acceptable shape with several symmetric cyclic voltammetric peaks, followed by calculating electrochemical factors. In addition, differential pulse voltammetry confirmed the Sudan I oxidation response with high sensitivity. The plot of oxidation peak currents versus different concentrations of Sudan I using a linear regression analysis was drawn to determine the Sudan I electroanalysis under optimized conditions. The results exhibited a low limit of detection (0.02 μM) and a broad linear dynamic range (0.07–415.0 μM). [ABSTRACT FROM AUTHOR]