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Pilot survey of expressed sequence tags (ESTs) from the asexual blood stages of Plasmodium vivax in human patients
Emilio F Merino, Carmen Fernandez-Becerra, Alda MBN Madeira, Ariane L Machado, Alan Durham, Arthur Gruber, Neil Hall, Hernando A del Portillo
Malaria Journal , 2003, DOI: 10.1186/1475-2875-2-21
Abstract: A pilot survey of expressed sequence tags (ESTs) from the asexual blood stages of P. vivax was performed. To do so, 1,184 clones from a cDNA library constructed with parasites obtained from 10 different human patients in the Brazilian Amazon were sequenced. Sequences were automatedly processed to remove contaminants and low quality reads. A total of 806 sequences with an average length of 586 bp met such criteria and their clustering revealed 666 distinct events. The consensus sequence of each cluster and the unique sequences of the singlets were used in similarity searches against different databases that included P. vivax, Plasmodium falciparum, Plasmodium yoelii, Plasmodium knowlesi, Apicomplexa and the GenBank non-redundant database. An E-value of <10-30 was used to define a significant database match. ESTs were manually assigned a gene ontology (GO) terminologyA total of 769 ESTs could be assigned a putative identity based upon sequence similarity to known proteins in GenBank. Moreover, 292 ESTs were annotated and a GO terminology was assigned to 164 of them.These are the first ESTs reported for P. vivax and, as such, they represent a valuable resource to assist in the annotation of the P. vivax genome currently being sequenced. Moreover, since the GC-content of the P. vivax genome is strikingly different from that of P. falciparum, these ESTs will help in the validation of gene predictions for P. vivax and to create a gene index of this malaria parasite.Plasmodium vivax is the most widely distributed human malaria and responsible for 70–80 million clinical cases each year and large socio-economical burdens for countries such as Brazil and India, where it is the most prevalent species [1]. Unfortunately, due to the problem of maintaining this parasite in continuous in vitro culture, the fact that vivax malaria is not as life threatening as falciparum malaria, the low parasitemias associated with natural human infections and the difficulty of adapting field isol
Genetic diversity of Plasmodium vivax in Kolkata, India
Jung-Ryong Kim, Mallika Imwong, Amitabha Nandy, Kesinee Chotivanich, Apichart Nontprasert, Naowarat Tonomsing, Ardhendu Maji, Manjulika Addy, Nick PJ Day, Nicholas J White, Sasithon Pukrittayakamee
Malaria Journal , 2006, DOI: 10.1186/1475-2875-5-71
Abstract: Blood from 151 patients with P. vivax infection diagnosed in Kolkata between April 2003 and September 2004 was genotyped at three polymorphic loci: the P. vivax circumsporozoite protein (pvcs), the merozoite surface protein 1 (pvmsp1) and the merozoite surface protein 3-alpha (pvmsp3-alpha).Analysis of these three genetic markers revealed that P. vivax populations in Kolkata are highly diverse. A large number of distinguishable alleles were found from three genetic markers: 11 for pvcs, 35 for pvmsp1 and 37 for pvmsp3-alpha. These were, in general, randomly distributed amongst the isolates. Among the 151 isolates, 142 unique genotypes were detected the commonest genotype at a frequency of less than 2% (3/151). The overall rate of mixed genotype infections was 10.6%.These results indicate that the P. vivax parasite population is highly diverse in Kolkata, despite the low level of transmission. The genotyping protocols used in this study may be useful for differentiating re-infection from relapse and recrudescence in studies assessing of malarial drug efficacy in vivax malaria.Malaria remains one of the most important communicable diseases in the world. Despite enormous control efforts over many decades malaria is still a significant health problem. It is estimated that around 300–500 million cases occur each year with one to three million deaths. The problem is compounded by multiple drug resistance in Plasmodium falciparum and chloroquine resistance in Plasmodium vivax [1]. The global burden of malaria due to P. vivax is 70–80 million cases annually. Vivax malaria is usually a non-lethal infection but its prolonged and recurrent infection can have major deleterious effects on personal well-being, growth and on the economic performance at the individual, family, community and national levels [2]. The recent emergence of chloroquine-resistant strains is of great concern [3-5].P. vivax causes about 60–65% of all malaria infections in India [6,7,42]. The frequency of re
The JAK-STAT Pathway Controls Plasmodium vivax Load in Early Stages of Anopheles aquasalis Infection  [PDF]
Ana C. Bahia,Marina S. Kubota,Antonio J. Tempone,Helena R. C. Araújo,Bruno A. M. Guedes,Alessandra S. Orfanó,Wanderli P. Tadei,Claudia M. Ríos-Velásquez,Yeon S. Han,Nágila F. C. Secundino,Carolina Barillas-Mury,Paulo F. P. Pimenta equal contributor ,Yara M. Traub-Csek? equal contributor
PLOS Neglected Tropical Diseases , 2011, DOI: 10.1371/journal.pntd.0001317
Abstract: Malaria affects 300 million people worldwide every year and 450,000 in Brazil. In coastal areas of Brazil, the main malaria vector is Anopheles aquasalis, and Plasmodium vivax is responsible for the majority of malaria cases in the Americas. Insects possess a powerful immune system to combat infections. Three pathways control the insect immune response: Toll, IMD, and JAK-STAT. Here we analyze the immune role of the A. aquasalis JAK-STAT pathway after P. vivax infection. Three genes, the transcription factor Signal Transducers and Activators of Transcription (STAT), the regulatory Protein Inhibitors of Activated STAT (PIAS) and the Nitric Oxide Synthase enzyme (NOS) were characterized. Expression of STAT and PIAS was higher in males than females and in eggs and first instar larvae when compared to larvae and pupae. RNA levels for STAT and PIAS increased 24 and 36 hours (h) after P. vivax challenge. NOS transcription increased 36 h post infection (hpi) while this protein was already detected in some midgut epithelial cells 24 hpi. Imunocytochemistry experiments using specific antibodies showed that in non-infected insects STAT and PIAS were found mostly in the fat body, while in infected mosquitoes the proteins were found in other body tissues. The knockdown of STAT by RNAi increased the number of oocysts in the midgut of A. aquasalis. This is the first clear evidence for the involvement of a specific immune pathway in the interaction of the Brazilian malaria vector A. aquasalis with P. vivax, delineating a potential target for the future development of disease controlling strategies.
Plasmodium vivax malaria presenting with severe thrombocytopenia
Makkar, Ravinder Pal Singh;Monga, Surabhi Mukhopadhyay Amitabh;Gupta, Ajay Kr.;
Brazilian Journal of Infectious Diseases , 2002, DOI: 10.1590/S1413-86702002000500008
Abstract: plasmodium falciparum and plasmodium vivax malaria are endemic infections in india and are commonly associated with mild hematological abnormalities. severe thrombocytopenia is common in isolated falciparum and mixed falciparum/vivax malaria, but is very rare in isolated p.vivax infection. we hereby report a case of severe thrombocytopenia (platelet count of 8x109/l) in a case of vivax malaria. this is only the second case ever reported in the literature of such profound thrombocytopenia in a case of isolated p.vivax malaria.
Plasmodium vivax malaria presenting with severe thrombocytopenia  [cached]
Makkar Ravinder Pal Singh,Monga Surabhi Mukhopadhyay Amitabh,Gupta Ajay Kr.
Brazilian Journal of Infectious Diseases , 2002,
Abstract: Plasmodium falciparum and Plasmodium vivax malaria are endemic infections in India and are commonly associated with mild hematological abnormalities. Severe thrombocytopenia is common in isolated falciparum and mixed falciparum/vivax malaria, but is very rare in isolated P.vivax infection. We hereby report a case of severe thrombocytopenia (platelet count of 8x10(9)/L) in a case of vivax malaria. This is only the second case ever reported in the literature of such profound thrombocytopenia in a case of isolated P.vivax malaria.
Plasmodium vivax malaria: An unusual presentation  [cached]
Kasliwal Prasad,Rao Manimala,Kujur Rash
Indian Journal of Critical Care Medicine , 2009,
Abstract: Acute renal failure, disseminated intravascular coagulation (DIC), acute respiratory distress syndrome (ARDS), hypoglycemia, coma, or epileptic seizures are manifestations of severe Plasmodium falciparum malaria. On the other hand, Plasmodium vivax malaria seldom results in pulmonary damage, and pulmonary complications are exceedingly rare. We report the case of a 42-year-old male living in a malaria-endemic area who presented with ARDS and was diagnosed as having Plasmodium vivax malaria. A diagnosis of Plasmodium vivax malaria was established by a positive Plasmodium LDH immunochromatographic assay while a negative PfHRP2 based assay ruled out P. falciparum malaria. After specific anti-plasmodial therapy and intensive supportive care, the patient recovered and was discharged from hospital. The use of NIPPV in vivax-malaria related ARDS was associated with a good outcome.
Multiplicity and Diversity of Plasmodium vivax Infections in a Highly Endemic Region in Papua New Guinea  [PDF]
Cristian Koepfli,Amanda Ross,Benson Kiniboro,Thomas A. Smith,Peter A. Zimmerman,Peter Siba,Ivo Mueller,Ingrid Felger
PLOS Neglected Tropical Diseases , 2011, DOI: 10.1371/journal.pntd.0001424
Abstract: Plasmodium vivax is highly endemic in the lowlands of Papua New Guinea and accounts for a large proportion of the malaria cases in children less than 5 years of age. We collected 2117 blood samples at 2-monthly intervals from a cohort of 268 children aged 1 to 4.5 years and estimated the diversity and multiplicity of P. vivax infection. All P. vivax clones were genotyped using the merozoite surface protein 1 F3 fragment (msp1F3) and the microsatellite MS16 as molecular markers. High diversity was observed with msp1F3 (HE = 88.1%) and MS16 (HE = 97.8%). Of the 1162 P. vivax positive samples, 74% harbored multi-clone infections with a mean multiplicity of 2.7 (IQR = 1–3). The multiplicity of P. vivax infection increased slightly with age (P = 0.02), with the strongest increase in very young children. Intensified efforts to control malaria can benefit from knowledge of the diversity and MOI both for assessing the endemic situation and monitoring the effects of interventions.
Population Structure and Transmission Dynamics of Plasmodium vivax in the Republic of Korea Based on Microsatellite DNA Analysis  [PDF]
Moritoshi Iwagami,Megumi Fukumoto,Seung-Young Hwang,So-Hee Kim,Weon-Gyu Kho ,Shigeyuki Kano
PLOS Neglected Tropical Diseases , 2012, DOI: 10.1371/journal.pntd.0001592
Abstract: Background In order to control malaria, it is important to understand the genetic structure of the parasites in each endemic area. Plasmodium vivax is widely distributed in the tropical to temperate regions of Asia and South America, but effective strategies for its elimination have yet to be designed. In South Korea, for example, indigenous vivax malaria was eliminated by the late 1970s, but re-emerged from 1993. We estimated the population structure and temporal dynamics of transmission of P. vivax in South Korea using microsatellite DNA markers. Methodology/Principal Findings We analyzed 255 South Korean P. vivax isolates collected from 1994 to 2008, based on 10 highly polymorphic microsatellite DNA loci of the P. vivax genome. Allelic data were obtained for the 87 isolates and their microsatellite haplotypes were determined based on a combination of allelic data of the loci. In total, 40 haplotypes were observed. There were two predominant haplotypes: H16 and H25. H16 was observed in 9 isolates (10%) from 1996 to 2005, and H25 in 27 (31%) from 1995 to 2003. These results suggested that the recombination rate of P. vivax in South Korea, a temperate country, was lower than in tropical areas where identical haplotypes were rarely seen in the following year. Next, we estimated the relationships among the 40 haplotypes by eBURST analysis. Two major groups were found: one composed of 36 isolates (41%) including H25; the other of 20 isolates (23%) including H16. Despite the low recombination rate, other new haplotypes that are genetically distinct from the 2 groups have also been observed since 1997 (H27). Conclusions/Significance These results suggested a continual introduction of P. vivax from other population sources, probably North Korea. Molecular epidemiology using microsatellite DNA of the P. vivax population is effective for assessing the population structure and transmission dynamics of the parasites - information that can assist in the elimination of vivax malaria in endemic areas.
Development, validation and evaluation of a rapid PCR-nucleic acid lateral flow immuno-assay for the detection of Plasmodium and the differentiation between Plasmodium falciparum and Plasmodium vivax  [cached]
Mens Petra F,Moers AntoinePHA,de Bes Laura M,Flint Jonathan
Malaria Journal , 2012, DOI: 10.1186/1475-2875-11-279
Abstract: Background Molecular tools are very sensitive and specific and could be an alternative for the diagnosis of malaria. The complexity and need for expensive equipment may hamper implementation and, therefore, simplifications to current protocols are warranted. Methods A PCR detecting the different Plasmodium species and differentiating between Plasmodium falciparum and Plasmodium vivax was developed and combined with a nucleic acid lateral flow immuno-assay (PCR-NALFIA) for amplicon detection. The assay was thoroughly evaluated for the analytical sensitivity and specificity in the laboratory, the robustness and reproducibility in a ring trial and accuracy and predictive value in a field trial. Results The analytical sensitivity and specificity were 0.978 (95% CI: 0.932–0.994) and 0.980 (95% CI: 0.924-0.997), respectively, and were slightly less sensitive for the detection of P. vivax than for P. falciparum. The reproducibility tested in three laboratories was very good (k = 0.83). This evaluation showed that the PCR machine used could influence the results. Accuracy was evaluated in Thailand and compared to expert microscopy and rapid diagnostic tests (RDTs). The overall and P. falciparum-specific sensitivity and specificity was good ranging from 0.86-1 and 0.95-0.98 respectively, compared to microscopy. Plasmodium vivax detection was better than the sensitivity of RDT, but slightly less than microscopy performed in this study. Conclusion PCR-NALFIA is a sensitive, specific and robust assay able to identify Plasmodium species with good accuracy. Extensive testing including a ring trial can identify possible bottlenecks before implementation and is therefore essential to perform in additon to other evaluations.
Microsatellite DNA Analysis Revealed a Drastic Genetic Change of Plasmodium vivax Population in the Republic of Korea During 2002 and 2003  [PDF]
Moritoshi Iwagami,Seung-Young Hwang,So-Hee Kim,So-Jung Park,Ga-Young Lee,Emilie Louise Akiko Matsumoto-Takahashi,Weon-Gyu Kho ,Shigeyuki Kano
PLOS Neglected Tropical Diseases , 2013, DOI: 10.1371/journal.pntd.0002522
Abstract: Background Vivax malaria was successfully eliminated in the Republic of Korea (South Korea) in the late 1970s, but it was found to have re-emerged from 1993. In order to control malaria and evaluate the effectiveness of malaria controls, it is important to develop a spatiotemporal understanding of the genetic structure of the parasite population. Here, we estimated the population structure and temporal dynamics of the transmission of Plasmodium vivax in South Korea by analyzing microsatellite DNA markers of the parasite. Methodology/Principal Findings We analyzed 14 microsatellite DNA loci of the P. vivax genome from 163 South Korean isolates collected from 1994 to 2008. Allelic data were used to analyze linkage disequilibrium (LD), genetic differentiation and population structure, in order to make a detailed estimate of temporal change in the parasite population. The LD analysis showed a gradual decrease in LD levels, while the levels of genetic differentiation between successive years and analysis of the population structure based on the Bayesian approach suggested that a drastic genetic change occurred in the South Korean population during 2002 and 2003. Conclusions/Significance Although relapse and asymptomatic parasite carriage might influence the population structure to some extent, our results suggested the continual introduction of P. vivax into South Korea through other parasite population sources. One possible source, particularly during 2002 and 2003, is North Korea. Molecular epidemiology using microsatellite DNA of the P. vivax population is effective for assessing the population structure and temporal dynamics of parasite transmission; information that can assist in the elimination of vivax malaria in endemic areas.
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