title: Improved detection of malaria cases in island settings of Vanuatu and Kenya by PCR that targets the Plasmodium mitochondrial cytochrome c oxidase III (cox3) gene.
abstract: Detection of sub-microscopic parasitemia is crucial for all malaria elimination programs. PCR-based methods have proven to be sensitive, but two rounds of amplification (nested PCR) are often needed to detect the presence of Plasmodium DNA. To simplify the detection process, we designed a nested PCR method whereby only the primary PCR is required for the detection of the four major human Plasmodium species. Primers designed for the detection of the fifth species, Plasmodium knowlesi, were not included in this study due to the absence of appropriate field samples. Compared to the standard 18S rDNA PCR method, our cytochrome c oxidase III (cox3) method detected 10-50% more cases while maintaining high sensitivities (1.00) for all four Plasmodium species in our samples from Vanuatu (n=77) and Kenya (n=76). Improvement in detection efficiency was more substantial for samples with sub-microscopic parasitemia (54%) than those with observable parasitemia (10-16%). Our method will contribute to improved malaria surveillance in low endemicity settings.
authors.affiliation: Department of Medical Zoology, Graduate School of Medicine, Osaka City University, 1-4-3, Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Isozumi
authors.affiliation: Department of Medical Zoology, Graduate School of Medicine, Osaka City University, 1-4-3, Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Fukui
authors.affiliation: Department of Medical Zoology, Graduate School of Medicine, Osaka City University, 1-4-3, Asahi-machi, Abeno-ku, Osaka 545-8585, Japan; Island Malaria Group, Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Nobels väg 16, SE 171 77 Stockholm, Sweden.
authors.forename: Akira
authors.initials: A
authors.lastname: Kaneko
authors.affiliation: Island Malaria Group, Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Nobels väg 16, SE 171 77 Stockholm, Sweden.
authors.forename: Chim W
authors.initials: CW
authors.lastname: Chan
authors.affiliation: Division of International Health, Research Promotion Project, Oita University Faculty of Medicine, Yufu 879-5593, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kawamoto
authors.affiliation: Radioisotope Centre, Graduate School of Medicine, Osaka City University, 1-4-3, Asahi-machi, Abeno-ku, Osaka 545-8585, Japan. Electronic address: mkimura@med.osaka-cu.ac.jp.
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Kimura
mesh_terms: D017931:DNA Primers; D016054:DNA, Protozoan; D003576:Electron Transport Complex IV / Q000235:genetics*; D050259:Genes, Mitochondrial; D006801:Humans; D007630:Kenya; D008288:Malaria / Q000175:diagnosis*; D018512:Parasitemia / Q000175:diagnosis*; D010961:Plasmodium / Q000235:genetics* / Q000302:isolation & purification*; D010963:Plasmodium falciparum / Q000235:genetics / Q000302:isolation & purification; D010966:Plasmodium vivax / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D009514:Vanuatu
chemical_list: D017931:DNA Primers; D016054:DNA, Protozoan; D003576:Electron Transport Complex IV
keywords: Human malaria; Malaria diagnosis; Mitochondrial DNA; Nested PCR; Plasmodium; cox3