Merozoite surface proteins (MSPs) of malaria parasites play critical roles during the erythrocyte invasion and so are potential candidates for malaria vaccine development. However, because MSPs are often under strong immune selection, they can exhibit extensive genetic diversity. The gene encoding the merozoite surface protein-3 (MSP-3) of Plasmodium falciparum displays 2 allelic types, K1 and 3D7. In Thailand, the allelic frequency of the P. falciparum msp-3 gene was evaluated in a single P. falciparum population in Tak at the Thailand and Myanmar border. However, no study has yet looked at the extent of genetic diversity of the msp-3 gene in P. falciparum populations in other localities. Here, we genotyped the msp-3 alleles of 63 P. falciparum samples collected from 5 geographical populations along the borders of Thailand with 3 neighboring countries (Myanmar, Laos, and Cambodia). Our study indicated that the K1 and 3D7 alleles coexisted, but at different proportions in different Thai P. falciparum populations. K1 was more prevalent in populations at the Thailand-Myanmar and Thailand-Cambodia borders, whilst 3D7 was more prevalent at the Thailand-Laos border. Global analysis of the msp-3 allele frequencies revealed that proportions of K1 and 3D7 alleles of msp-3 also varied in different continents, suggesting the divergence of malaria parasite populations. In conclusion, the variation in the msp-3 allelic patterns of P. falciparum in Thailand provides fundamental knowledge for inferring the P. falciparum population structure and for the best design of msp-3 based malaria vaccines.
Antigens, Protozoan/*genetics ; *Gene Frequency ; *Genetic Variation ; Genotype ; Humans ; Malaria, Falciparum/epidemiology/*parasitology ; Plasmodium falciparum/classification/*genetics/isolation & purification ; Polymorphism, Genetic ; Protozoan Proteins/*genetics ; Thailand/epidemiology

Mitochondrial genome sequence of malaria parasites has served as a potential marker for inferring evolutionary history of the Plasmodium genus. In Plasmodium falciparum, the mitochondrial genome sequences from around the globe have provided important evolutionary understanding, but no Indian sequence has yet been utilized. We have sequenced the whole mitochondrial genome of a single P. falciparum field isolate from India using novel primers and compared with the 3D7 reference sequence and 1 previously reported Indian sequence. While the 2 Indian sequences were highly divergent from each other, the presently sequenced isolate was highly similar to the reference 3D7 strain.
DNA, Mitochondrial/*chemistry/*genetics ; Genetic Variation ; *Genome, Mitochondrial ; Humans ; India ; Malaria, Falciparum/parasitology ; Molecular Sequence Data ; Plasmodium falciparum/*genetics/isolation & purification ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid

OBJECTIVETo survey malaria prevalence in Sarbaz from April 2009 to October 2010.

METHODSEpidemiological data of 1 464 confirmed malarial patients were analyzed according to demographic status, sex, age, nationality, isolated species and residence place.

RESULTSThe majority of patients were male 950 (64.8%) but 514 (35.2%) were female. 82.5% of patients were Iranian, 14% Pakistani immigrants, and 3.5% Afghan immigrants. Data collected showed that 90% of isolated species were Plasmodium vivax, 7.8% Plasmodium falciparum, and 2.2% Plasmodium malariae and mixed species.

CONCLUSIONSTherefore, it is crystal clear that refugees should be prohibited by government and controlled by experts in health centers in order to campaign effectively with this life threating disease.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Demography ; Ethnic Groups ; Female ; Humans ; Infant ; Infant, Newborn ; Iran ; epidemiology ; Malaria ; epidemiology ; parasitology ; Male ; Middle Aged ; Plasmodium falciparum ; isolation & purification ; Plasmodium malariae ; isolation & purification ; Plasmodium vivax ; isolation & purification ; Prevalence ; Young Adult

Local malaria transmission in the United Arab Emirates (UAE) came to an end in 1997. Nevertheless, UAE has been subjected to substantial importation of malaria cases from abroad, concerning both UAE nationals and immigrants from malarious countries with a total number of 2,119 cases in 2007. To evaluate a new DNA extraction technique using nested PCR, blood samples were collected from 132 individuals who presented to Infectious Diseases Department in Rashid Hospital, Dubai, and Central Department of Malaria Control with fever and persistent headache. Giemsa-stained blood films and ELISA test for malaria antibodies were carried out for detection of Plasmodium infection. Plasmodium infections were identified with the genus-specific primer set and species differentiation using nested PCR. A rapid procedure for diagnosis of malaria infections directly from dried blood spots using for the first time DNA extract from FTA Elute cards was evaluated in contrast to extraction techniques using FTA classic cards and rapid boiling technique. Our new simple technique for DNA extraction using FTA Elute cards was very sensitive giving a sensitivity of 100% compared to 94% using FTA classic cards and 62% in the rapid boiling technique. No complex preparation of blood samples was required prior to the amplification. The production cost of DNA isolation in our PCR assay was much less in comparable to that of other DNA extraction protocols. The nested PCR detected plasmodial infection and could differentiate P. falciparum from P. vivax, and also detected the mixed infection.
Animals ; DNA, Protozoan/genetics/*isolation & purification ; *Emigrants and Immigrants/statistics & numerical data ; *Genetic Techniques ; Humans ; Malaria, Falciparum/epidemiology/*parasitology ; Plasmodium falciparum/genetics/*isolation & purification ; Polymerase Chain Reaction/*methods ; United Arab Emirates/epidemiology

Local malaria transmission in the United Arab Emirates (UAE) came to an end in 1997. Nevertheless, UAE has been subjected to substantial importation of malaria cases from abroad, concerning both UAE nationals and immigrants from malarious countries with a total number of 2,119 cases in 2007. To evaluate a new DNA extraction technique using nested PCR, blood samples were collected from 132 individuals who presented to Infectious Diseases Department in Rashid Hospital, Dubai, and Central Department of Malaria Control with fever and persistent headache. Giemsa-stained blood films and ELISA test for malaria antibodies were carried out for detection of Plasmodium infection. Plasmodium infections were identified with the genus-specific primer set and species differentiation using nested PCR. A rapid procedure for diagnosis of malaria infections directly from dried blood spots using for the first time DNA extract from FTA Elute cards was evaluated in contrast to extraction techniques using FTA classic cards and rapid boiling technique. Our new simple technique for DNA extraction using FTA Elute cards was very sensitive giving a sensitivity of 100% compared to 94% using FTA classic cards and 62% in the rapid boiling technique. No complex preparation of blood samples was required prior to the amplification. The production cost of DNA isolation in our PCR assay was much less in comparable to that of other DNA extraction protocols. The nested PCR detected plasmodial infection and could differentiate P. falciparum from P. vivax, and also detected the mixed infection.
Animals ; DNA, Protozoan/genetics/*isolation & purification ; *Emigrants and Immigrants/statistics & numerical data ; *Genetic Techniques ; Humans ; Malaria, Falciparum/epidemiology/*parasitology ; Plasmodium falciparum/genetics/*isolation & purification ; Polymerase Chain Reaction/*methods ; United Arab Emirates/epidemiology

In order to determine the status of malaria among schoolchildren on Kome Island (Lake Victoria), near Mwanza, Tanzania, a total of 244 schoolchildren in 10 primary schools were subjected to a blood survey using the fingerprick method. The subjected schoolchildren were 123 boys and 121 girls who were 6-8 years of age. Only 1 blood smear was prepared for each child. The overall prevalence of malaria was 38.1% (93 positives), and sex difference was not remarkable. However, the positive rate was the highest in Izindabo Primary School (51.4%) followed by Isenyi Primary School (48.3%) and Bugoro Primary School (46.7%). The lowest prevalence was found in Muungano Primary School (16.7%) and Nyamiswi Primary School (16.7%). These differences were highly correlated with the location of the school on the Island; those located in the peripheral area revealed higher prevalences while those located in the central area showed lower prevalences. Plasmodium falciparum was the predominant species (38.1%; 93/244), with a small proportion of them mixed-infected with Plasmodium vivax (1.6%; 4/244). The results revealed that malaria is highly prevalent among primary schoolchildren on Kome Island, Tanzania, and there is an urgent need to control malaria in this area.
Blood/parasitology ; Child ; Coinfection/epidemiology/parasitology ; Cross-Sectional Studies ; Female ; Humans ; Malaria/*epidemiology/parasitology ; Male ; Microscopy ; Plasmodium falciparum/*isolation & purification ; Plasmodium vivax/*isolation & purification ; Prevalence ; Tanzania/epidemiology ; Topography, Medical

The traditional light microscopy has limitations for precise growth assays of malaria parasites in culture or for assessment of new compounds for antimalarial activity; the speed and high reproducibility of flow cytometry can overcome these limitations. A flow cytometric method using PicoGreen, a DNA-binding fluorochrome, was developed with optimal precision suitable for performing growth assays of low-parasitemia field isolates. In addition, intra- and inter-person reproducibility of the flow cytometric and the microscopic method were compared in order to quantitatively demonstrate the improved precision. RNase treatment contributed to the precision of the flow cytometric measurements by enhancing the signal-to-noise ratios. Coefficients of variation of the method were smaller than 10% for 0.1% or higher parasitemia samples. The intra- and inter-person coefficients of variation of the flow cytometric method were three to six times smaller than those of the microscopic method. The flow cytometric method developed in this study yielded substantially more precise results than the microscopic method, allowing determination of parasitemia levels of 0.1% or higher, with coefficients of variation smaller than 10%. Thus, the PicoGreen method could be a reliable high sensitivity assay for analysis of low parasitemia samples and might be applied to a high throughput system testing antimalarial drug activity.
*Flow Cytometry ; Fluorescent Dyes/chemistry ; Humans ; *Microscopy ; Organic Chemicals/chemistry ; Parasitemia/*diagnosis ; Plasmodium falciparum/*isolation & purification ; Reproducibility of Results ; Ribonucleases/metabolism ; Signal-To-Noise Ratio

Animals ; Apraxias ; congenital ; Cogan Syndrome ; diagnosis ; etiology ; Coma ; Diagnosis, Differential ; Humans ; Malaria, Cerebral ; complications ; diagnosis ; parasitology ; Male ; Middle Aged ; Plasmodium falciparum ; isolation & purification ; Tomography, X-Ray Computed

BACKGROUND: Although malaria-specific antibody or antigen test is useful for the diagnosis of malaria infection, its cost-effectiveness has to be concerned in the area where malaria prevalence is very low. We created a panel test composed of malaria non-specific parameters, namely hematology autoanalyzer-derived results with or without addition of HDL-cholesterol data, and evaluated its usefulness in comparison with malaria-specific antibody test. METHODS: For 395 patients tested for malaria smear, the hematology parameters such as platelet count, NRBC (%) and VCS (volume, conductivity, scattering) parameters of WBC, and HDL-cholesterol data were analyzed. Statistical significance of each parameter and that of panel test with or without addition of HDL-cholesterol were evaluated. RESULTS: Malaria antibody test showed sensitivity of 97.1% and specificity of 99.1%. Each parameter of platelet count, NRBC (%), D parameter and HDL-cholesterol showed sensitivity of 86.8%, 41.2%, 81.8%, and 70.6%, and specificity of 85.9%, 96.3%, 72.3%, and 81.7%, respectively. Panel test without including HDL-cholesterol showed sensitivity of 91.2% and specificity of 81.6%, and that including HDL-cholesterol showed sensitivity of 91.2% and specificity of 86.2%. CONCLUSIONS: The malaria non-specific panel test composed of hematology autoanalyzer-derived parameters showed relatively good, but slightly lower sensitivity than that of malaria-specific antibody test. It might be used as a screening test for the diagnosis of malaria infection, and addition of HDL cholesterol improved little the usefulness of the panel test.
Animals ; Autoanalysis ; Biological Markers ; Cholesterol, HDL/*blood ; Diagnosis, Differential ; Hematologic Tests/economics/utilization ; Humans ; Malaria, Falciparum/blood/*diagnosis ; Plasmodium falciparum/isolation & purification ; ROC Curve ; Reagent Kits, Diagnostic ; Sensitivity and Specificity

The incidence of imported malaria has been increasing in Korea. We reviewed data retrospectively to evaluate the epidemiology, clinical features, and outcomes of imported malaria from 1995 to 2007 in a university hospital. All patients diagnosed with imported malaria were included. Imported malaria was defined as a positive smear for malaria that was acquired in a foreign country. A total of 49 patients (mean age, 35.7 year; M : F = 38 : 11) were enrolled. The predominant malarial species was Plasmodium falciparum (73.5%), and the most frequent area of acquisition was Africa (55.1%), followed by Southeast Asia (22.4%) and South Asia (18.4%). Fourteen-patients (30.6%) suffered from severe malaria caused by P. falciparum and 1 patient (2.0%) died of multiorgan failure. Most of the patients were treated with mefloquine (79.2%) or quinine (10.2%); other antimalarial agents had to be given in 13.2% treated with mefloquine and 44.4% with quinine due to adverse drug events (ADEs). P. falciparum was the most common cause of imported malaria, with the majority of cases acquired from Africa, and a significant number of patients had severe malaria. Alternative antimalarial agents with lower rates of ADEs might be considered for effective treatment instead of mefloquine and quinine.
Adult ; Animals ; Antimalarials/adverse effects/therapeutic use ; Female ; Humans ; Korea/epidemiology ; Malaria, Falciparum/drug therapy/epidemiology/*parasitology ; Male ; Middle Aged ; Plasmodium falciparum/drug effects/isolation & purification ; Retrospective Studies ; *Travel