| malaria in lakshadweep islands. | | 1978 | 363613 |
| malaria transmission by anopheles subpictus (diptera: culicidae) in a new irrigation project in sri lanka. | indoor resting anopheles subpictus in a new irrigation scheme in sri lanka were investigated during 1989-1990 for malaria infection by dissection and elisa, and human feeding rates by elisa analysis of blood meals. indoor resting abundance was 22.3 females per house per 15-min catch in april-june 1989, 2.2 in november-december 1989, and 7.5 in april-june 1990. elisa-based malaria infection rates (plasmodium vivax and p. falciparum combined) were 1.4% during april-june and 3.2% during november-de ... | 1992 | 1495065 |
| genetic complexity of plasmodium vivax parasites in individual human infections analyzed with monoclonal antibodies against variant epitopes on a single parasite protein. | monoclonal antibodies against variant epitopes of a highly polymorphic protein (pv200) in schizonts of plasmodium vivax have been used to analyze the variety of genetically distinct populations of parasites present in the peripheral blood of individual p. vivax infections in sri lanka. in 9 out of 10 isolates of freshly drawn p. vivax infected blood from different individuals, parasites of only 1 pv200 serotype was found within each individual infection, even though parasites were serotypically ... | 1990 | 1690521 |
| [malaria in 1989 in a village in the highland plateaux of madagascar. parasitologic and clinical data obtained in a longitudinal study of a population representative of this region]. | | 1990 | 2078077 |
| [preliminary study on malaria transmission at the end of the rainy season in mahitsy near tananarive]. | this survey carried out from march to june 1989, demonstrated the important part of an. funestus in malaria transmission, in mahisty, a village near the malagasy capital city. end of march, the number of an. funestus bites reached 6 per man per night, and only 0.75 for an. gambiae s.l. in march a mean of 23 an. funestus per room were found as indoor resting mosquitoes. one indoor resting an. funestus, caught in june, was positive against p. vivax by elisa. observed of 52 indoor-resting an. funes ... | 1990 | 2078087 |
| reproduction rates of infection during the 1967-1968 p. vivax malaria epidemic in sri lanka (ceylon). | | 1973 | 4574924 |
| [preliminary study of the prevalence of malaria infestation in the province of tamatave]. | | 1982 | 6764610 |
| the madagascar strain of plasmodium vivax. | | 1980 | 7016054 |
| letter: delayed attacks of malaria in visitors to the tropics. | | 1973 | 4591006 |
| seroepidemiological evidence of eradication of malaria from mauritius. | | 1973 | 4125305 |
| [status of malarial endemic in nosy-be in february, 1984]. | | 1986 | 3541817 |
| a metropolitan hospital in a non-endemic area provides a sampling pool for epidemiological studies on vivax malaria in sri lanka. | an analysis of records of 494 malaria patients admitted to the general hospital in colombo (the capital of sri lanka where malaria transmission is not known to occur) from 1981 to 1984 is presented and compared with national malaria data from the entire country. the incidence of predominantly plasmodium vivax malaria rose sharply over the 3 years; its species distribution and seasonal variation in patients in the general hospital, colombo (ghc) generally reflected the disease pattern in the coun ... | 1987 | 3318015 |
| polymorphism at the merozoite surface protein-3alpha locus of plasmodium vivax: global and local diversity. | allelic diversity at the plasmodium vivax merozoite surface protein-3alpha (pvmsp-3alpha) locus was investigated using a combined polymerase chain reaction/restriction fragment length polymorphism (pcr/rflp) protocol. symptomatic patient isolates from global geographic origins showed a high level of polymorphism at the nucleotide level. these samples were used to validate the sensitivity, specificity, and reproducibility of the pcr/rflp method. it was then used to investigate pvmsp3alpha diversi ... | 1999 | 10548283 |
| modulation of human malaria transmission by anti-gamete transmission blocking immunity. | natural plasmodium vivax malaria infections in man evoke anti-gamete transmission blocking antibodies which influence the infectivity of malaria patients to the vector mosquito. in this study, entomological, immunological and parasitological data obtained through the monitoring of an epidemic of human vivax malaria in sri lanka were used in a mathematical simulation to assess the effect of naturally induced transmission blocking immunity on malaria transmission. a mathematical model to describe ... | 1988 | 3076711 |
| the malaria epidemic in antananarivo observed from pediatric service "a" of the befelatanana general hospital. | a recent malaria epidemic striking antananarivo, the capital city of madagascar, is shown from hospital records of pediatric service "a" of the befelatanana general hospital. from 1980 to 1988 malaria cases in this hospital service increased from 0.9% to 14.4% of all admissions (on average 1785 per year). the unexpected expansion is observed in 1984, 1985 and 1986 and since that time malaria has apparently maintained a stable endemic level. malaria mortality as a proportion of general mortality ... | 1989 | 2487897 |
| malaria transmission and vector biology in manarintsoa, high plateaux of madagascar. | to evaluate the factors which determine the transmission level of falciparum malaria, entomological and parasitological surveys were conducted from october 1988 to february 1990 in manarintsoa in the central highland plateaux of madagascar. mosquitoes were collected for 928 man-nights in pit shelters and indoor resting sites. malaria vectors were anopheles arabiensis and an. funestus, with no evidence of the presence of an. gambiae sensu stricto. vectors were mainly exophilic and zoophilic. the ... | 1990 | 2202220 |
| human t cell proliferative responses to plasmodium vivax antigens: evidence of immunosuppression following prolonged exposure to endemic malaria. | human t cell proliferative responses, of 33 adult sri lankans convalescing from plasmodium vivax infections, to several p. vivax antigens (i.e. a soluble extract of asexual erythrocytic stage parasites and two cloned antigens that are potential vaccine candidates pv200 and gam-1) were assessed. the peripheral blood mononuclear cell proliferative responses to the soluble extract of p. vivax, as assessed by studying both the proportion of responders and the degree of the response, were significant ... | 1990 | 2196178 |
| characteristics of malaria transmission in kataragama, sri lanka: a focus for immuno-epidemiological studies. | parasitological and entomological parameters of malaria transmission were monitored for 17 months in 3,625 residents in a plasmodium vivax malaria endemic region in southern sri lanka; the study area consisted of 7 contiguous villages where routine national malaria control operations were being conducted. malaria was monitored in every resident; fever patients were screened and 4 periodical mass blood surveys were conducted. an annual malaria incidence rate of 23.1% was reported during the perio ... | 1990 | 2184688 |
| antibody responses to plasmodium falciparum and p. vivax sporozoites in areas with stable and unstable malaria. | availability of synthetic and recombinant peptides reproducing the repetitive regions of the circumsporozoite (cs) proteins of plasmodium falciparum and p. vivax has allowed the development of assays for the detection of specific antibodies and of potential subunit vaccines. knowledge of the immune responses to malaria sporozoites is a prerequisite for the optimal design of a sporozoite antigen-based vaccine. studies carried out in areas with stable p. falciparum malaria (united republic of tanz ... | 1990 | 2094587 |
| [a case of congenital malaria with atypical expression of plasmodium vivax originating from madagascar]. | | 1990 | 2078076 |
| infectious reservoir of plasmodium vivax and plasmodium falciparum malaria in an endemic region of sri lanka. | the infectious reservoir of plasmodium vivax and p. falciparum in a malaria endemic region in sri lanka was defined in a population of 3,625 by directly feeding mosquitoes on a sample of infected individuals during a period of 17 months. the malaria case incidence in this population was concurrently monitored. p. vivax gametocyte densities were highest in the youngest age groups, and decreased steadily with increasing age. however, the infectivity per gametocyte appeared to be lower in the young ... | 1991 | 1951856 |
| anopheline ecology and malaria infection during the irrigation development of an area of the mahaweli project, sri lanka. | a study on adult anopheline ecology and malaria vector incrimination was carried out from 1986 to 1989 during irrigation development in an area of the mahaweli project in eastern sri lanka. eleven potential vector species were collected resting indoors or by using human or bovid bait, and from light trap catches. overall, anopheles vagus (donitz), an. annularis (van der wulp), and an. subpictus (grassi) were the most prevalent, and an. culicifacies (giles) and an. barbirostris (van der wulp) wer ... | 1991 | 1877717 |
| a randomized, double-blind, placebo-controlled, clinical trial of the impact of malaria prevention on the educational attainment of school children. | a double-blind, placebo-controlled trial of nine months duration was carried out to investigate the impact of malaria and its prevention on the educational attainment of school children in a malaria-endemic area in southern sri lanka where both plasmodium falciparum and p. vivax infections are prevalent. a total of 587 children attending grades 1-5 in four schools and resident in the area were randomly allocated to chloroquine (n = 295) and placebo (n = 292) arms. language and mathematics scores ... | 2006 | 16525095 |
| clustering of malaria infections within an endemic population: risk of malaria associated with the type of housing construction. | the occurrence of malaria infections due to plasmodium vivax and p. falciparum was monitored in a population of 3,023 people living in six contiguous villages in kataragama, an area of endemic malaria in southern sri lanka, over a period of 17 months. the annual incidence of malaria in this population during the study period was 25.8%. malaria attacks were clustered, occurring more frequently than expected in certain individuals and housing groups and less frequently than expected in others. in ... | 1991 | 1867350 |
| a mathematical model for plasmodium vivax malaria transmission: estimation of the impact of transmission-blocking immunity in an endemic area. | we have developed a multi-state mathematical model to describe the transmission of plasmodium vivax malaria; the model accommodates variable transmission-blocking/enhancing immunity during the course of a blood infection, a short memory for boosting immunity, and relapses. using the model, we simulated the incidence of human malaria, sporozoite rates in the vector population, and the level of transmission-blocking immunity for the infected population over a period of time. field data from an epi ... | 1991 | 1786621 |
| immune responses against sexual stages of plasmodium vivax during human malarial infections in sri lanka. | during natural infections of p. vivax malaria a variety of immune responses to the infection affect infectivity of the parasites to mosquitoes. sexual stage antigens present in the blood stage parasites induce antibodies which may either enhance or suppress the infectivity of the sexual parasites to mosquitoes. subsequent infections of p. vivax do not, unless occurring within less than 4 months, boost this response indicating a very short immune memory for the relevant antigens. blood infection ... | 1991 | 1688139 |
| anti-circumsporozoite protein antibodies measure age related exposure to malaria in kataragama, sri lanka. | antibodies to two peptides ddaad and (nanp)40 representing the repetitive sequence of circumsporozoite antigens (cs protein) of p. vivax and p. falciparum respectively were measured in a cohort of 149 and 107 individuals respectively at four, 6 monthly blood surveys performed on residents of kataragama, a p. vivax malaria endemic region in southern sri lanka. the prevalence of antibodies to the cs protein of both species was relatively low being less than 20% to either peptide in the population ... | 1992 | 1557232 |
| [malaria in the dunkerque hospital center from december 1979 to december 1990]. | seventy-one cases of malaria were diagnosed in the hospital of dunkerque from 1979 to 1990. forty-five patients have been infected in the comores islands. among the 24 other imported cases, 17 (71%) have been contaminated in western or central africa. one case of congenital malaria and one of malaria acquired by blood transfusion are also reported. plasmodium falciparum was detected in 84.5% of the patients. the four human species were found among the comorians. two cases with abnormal forms of ... | 1992 | 1443798 |
| a case of autochthonous plasmodium vivax malaria, corsica, august 2006. | | 2006 | 17213553 |
| transmission blocking immunity to human plasmodium vivax malaria in an endemic population in kataragama, sri lanka. | serum effects on gametocyte infectivity, that is, transmission blocking/enhancing immunity, were measured in the sera of 196 acute plasmodium vivax patients who were residents of a malaria region in kataragama, southern sri lanka. direct mosquito feedings were also performed on 170 of these patients. sera of about 48% of patients suppressed gametocyte infectivity significantly (by more than 75%) and of a smaller proportion (12%) had pronounced infectivity enhancing effects. transmission immunity ... | 1992 | 1437231 |
| high seasonal malaria transmission rates in the intermediate rainfall zone of sri lanka. | malaria transmission was studied at nikawehera, a long-established farming village, located in the intermediate rainfall zone of sri lanka. observations were made over a 12-month period (october-september) that included the main rainy season which occurred during the north-east monsoon in november-january. anolpheles culicifacies, the recognized vector of malaria in sri lanka, was the predominant anopheline mosquito collected by human night baiting at nikawehera. high entomological inoculation r ... | 1992 | 1304700 |
| plasmodium vivax dhfr and dhps mutations in isolates from madagascar and therapeutic response to sulphadoxine-pyrimethamine. | four of five plasmodium species infecting humans are present in madagascar. plasmodium vivax remains the second most prevalent species, but is understudied. no data is available on its susceptibility to sulphadoxine-pyrimethamine, the drug recommended for intermittent preventive treatment during pregnancy. in this study, the prevalence of p. vivax infection and the polymorphisms in the pvdhfr and pvdhps genes were investigated. the correlation between these polymorphisms and clinical and parasit ... | 2008 | 18302746 |
| plasmodium vivax resistance to chloroquine in madagascar: clinical efficacy and polymorphisms in pvmdr1 and pvcrt-o genes. | no data were available concerning plasmodium vivax resistance to chloroquine (cq) in madagascar. we investigated the therapeutic efficacy of cq in p. vivax malaria, the prevalence of mutations in the pvcrt-o and pvmdr1 genes before treatment, and the association between mutant parasites and the clinical response of the patients to cq treatment. clinical isolates were collected at six sentinel sites located in the three epidemiological strata for malaria throughout madagascar in 2006. patients we ... | 2008 | 18809933 |
| genotyping of plasmodium vivax infections in sri lanka using pvmsp-3alpha and pvcs genes as markers: a preliminary report. | plasmodim vivax malaria accounts for more than 90% of malaria cases in sri lanka. there is limited information on the genetic heterogeneity of p. vivax in endemic areas of the country. here we have assessed the potential of two p. vivax genes as genetic markers for their use in genotyping parasites collected from the field. dna extracted from geimsa-stained p. vivax positive slides were genotyped at two polymorphic loci: the p. vivax merozoite surface protein 3- alpha (pvmsp-3alpha) and circumsp ... | 2008 | 18948880 |
| [can the thick drop/smear examination for malaria be replaced by a rapid diagnostic test in first intention? the mayotte experience]. | malaria is a public health problem in the french island of mayotte (160,000 inhabitants) in the indian ocean. in the late 1990, resistance to chloroquine greatly increased, and so did the number of malaria cases, so that a new health policy had to be adopted. since 2001, the initial smear/thick drop examination, the results of which took too long to obtain, has systematically been replaced by a rapid diagnosis test (optimal it diamed) in all hospitals and public health centers. | 2009 | 18951743 |
| circulating stable antigens at higher levels down-regulate antibody responses to plasmodium falciparum. | a study involving 169 schoolchildren (5-14 years old) living in manarintsoa near antananarivo (madagascar, east africa) was performed during the seasonal malaria transmission period. for the whole population examined, the prevalence of plasmodium falciparum and the rates of spleen enlargement and of circulating stable antigen (s-ag) were found to be 60.9%, 71.7%, and 46.8%, respectively. the prevalence of igg antibody to resa (ring-infected erythrocyte surface antigen) was 42.7% and that of igg ... | 1993 | 8475036 |
| plasmodium vivax malaria in sri lanka: transmission, disease and immunity. | we have established a study site in a malaria endemic region around kataragama in the south of sri lanka. a population of about 3,000 individuals in a group of villages around kataragama have been provided with access to a small field clinic enabling us to monitor aspects of malarial infection under conditions of natural transmission. at the present time, both plasmodium falciparum and plasmodium vivax are prevalent to a similar degree although prior to about five years ago p. falciparum had bee ... | 1993 | 8233604 |
| humoral and cellular immune responses to the circumsporozoite protein of plasmodium vivax in madagascar. | plasmodium vivax malaria is prevalent during the rainy season in the central highlands of madagascar. in april 1991, we investigated the cellular and antibody immune responses of 53 inhabitants of manarintsoa, a village in this area, to four antigens corresponding to b and t cell epitopes of the p. vivax circumsporozoite (cs) protein. cellular responses were assessed by lymphocyte proliferation assay as well as by detection of interferon-gamma and interleukin-2 production in vitro. cell culture ... | 1993 | 7683178 |
| antibodies to epitopes on merozoite and sporozoite surface antigens as serologic markers of malaria transmission: studies at a site in the dry zone of sri lanka. | antibodies against repetitive epitopes on plasmodium falciparum and p. vivax circumsporozoite (cs) proteins and epitopes on the 45-kd and 185-200-kd p. falciparum merozoite surface antigens were measured by radioimmunoassay in weheragala, a malaria-endemic site in the dry zone of sri lanka. antibodies were measured in sera collected in february at the end of the main malaria transmission season and three months later in may during the low transmission period. ninety-seven percent of the sample p ... | 1994 | 7515593 |
| congenital malaria due to plasmodium vivax: a case report from sri lanka. | a case of plasmodium vivax malaria in an eight-week-old infant in colombo is documented, with epidemiological and circumstantial evidence which strongly supports a transplacental route of infection. the malarial antibody levels detected by the indirect fluorescent antibody technique in both mother and child are discussed in terms of the present epidemiological pattern of malaria in the country. we also comment on the species incidence of congenital malaria, this case being the first caused by p. ... | 1982 | 7043805 |
| demonstration of anti-disease immunity to plasmodium vivax malaria in sri lanka using a quantitative method to assess clinical disease. | clinical immunity to malaria was studied by quantifying the intensity of symptoms as well as by measurement of several hematologic indicators of pathology (the erythrocyte sedimentation rate [esr], serum bilirubin, reticulocyte count, plasma tumor necrosis factor-alpha [tnf-alpha], and blood glucose levels) in 39 plasmodium vivax malaria patients exposed to endemic malaria in southern sri lanka, and for comparison in 43 nonimmune patients who were residents of nonmalarious regions of the country ... | 1998 | 9502605 |
| clinical diagnosis of uncomplicated malaria in sri lanka. | to assess the possibility of developing a protocol for the clinical diagnosis of malaria, a study was done at the regional laboratory of the anti-malaria campaign in puttalam, sri lanka. of a group of 502 patients, who suspected they were suffering from malaria, 97 had a positive blood film for malaria parasites (71 plasmodium vivax and 26 p. falciparum). there were no important differences in signs and symptoms between those with positive and those with negative blood films. it is argued that i ... | 1998 | 9886105 |
| malaria vectors in a traditional dry zone village in sri lanka. | malaria transmission by anopheline mosquitoes was studied in a traditional tank-irrigation-based rice-producing village in the malaria-endemic low country dry zone of northcentral sri lanka during the period august 1994-february 1997. adult mosquitoes were collected from human and bovid bait catches, bovid-baited trap huts, indoor catches, and pit traps. mosquito head-thoraces were tested for the presence of plasmodium falciparum and p. vivax, and blood-engorged abdomens for the presence of huma ... | 1999 | 10466971 |
| quantifying genetic and nongenetic contributions to malarial infection in a sri lankan population. | explaining the causes of variation in the severity of malarial disease remains a major challenge in the treatment and control of malaria. many factors are known to contribute to this variation, including parasite genetics, host genetics, acquired immunity, and exposure levels. however, the relative importance of each of these to the overall burden of malarial disease in human populations has not been assessed. here, we have partitioned variation in the incidence of malarial infection and the cli ... | 2000 | 11035799 |
| control of malaria vectors with the insect growth regulator pyriproxyfen in a gem-mining area in sri lanka. | the study was conducted in eight adjacent villages in central sri lanka where there are many shallow pits dug by gem miners that fill with water. these become breeding places of the main malarial vector anopheles culicifacies, and of the second most important vector anopheles subpictus, but not of anopheles varuna, the third most important vector. with the help of local volunteers, data on the adult populations of these three species was collected by various standard methods, and data on the inc ... | 2001 | 11700185 |
| efficacy of a five-day course of primaquine in preventing relapses in plasmodium vivax malaria--a pilot study. | | 2003 | 12795021 |
| sri lanka malaria maps. | despite a relatively good national case reporting system in sri lanka, detailed maps of malaria distribution have not been publicly available. | 2003 | 12914667 |
| the impact of repeated malaria attacks on the school performance of children. | the impact of repeated malarial infections on the school performance of children was investigated in 571 school children 6-14 years of age in a malaria-endemic area in southern sri lanka where both plasmodium falciparum and p. vivax infections are prevalent. malaria infections confirmed by microscopy were monitored over a six-year period. school performance was assessed by two specially designed, school grade-specific, test papers for sinhala language and mathematics. the scores for sinhala lang ... | 2003 | 14740872 |
| a cost analysis of the use of the rapid, whole-blood, immunochromatographic p.f/p.v assay for the diagnosis of plasmodium vivax malaria in a rural area of sri lanka. | between may 2001 and march 2002, a prospective study was conducted in a malaria-endemic area of sri lanka, to determine the cost implications of using the immunochromatographic p.f/p.v test to detect plasmodium vivax infection. all consecutive subjects aged >5 years who presented with a history of fever were recruited. each was checked for p. vivax infection by the standard microscopical examination of bloodsmears and by the immunochromatographic test (ict). the costs of diagnosis using each met ... | 2004 | 15000725 |
| vectors and malaria transmission in a gem mining area in sri lanka. | anopheline vectors of malaria were studied in the kaluganga gem mining area in the dry zone of central sri lanka. adult mosquitoes were collected using cattle-baited huts and nets, pyrethrum spray sheets, window exit traps and light traps and partial and full-night human landing collections over a period of 17 mo. the collections produced a total of 13,591 anophelines belonging to 14 species. using elisa for circumsporozoite proteins of plasmodium vivax and p. falciparum, anopheles culicifacies, ... | 2004 | 15707286 |
| some characteristics of the larval breeding sites of anopheles culicifacies species b and e in sri lanka. | anopheles culicifacies giles, the major malaria vector in sri lanka, exists as a species complex comprising two sympatric sibling species--species b and e. species e is reported to be the major vector of plasmodium vivax and p. falciparum parasites in sri lanka, whilst species b is a poor or nonvector as in india. knowledge of the breeding habits of the two sibling species can help in designing optimal vector control strategies. hence, a survey was conducted in sri lanka to study the preferentia ... | 2005 | 16161699 |
| natural human antibody responses to plasmodium vivax apical membrane antigen 1 under low transmission and unstable malaria conditions in sri lanka. | plasmodium vivax apical membrane antigen 1, an important malaria vaccine candidate, was immunogenic during natural malaria infections in sri lanka, where low transmission and unstable malaria conditions prevail. antibody prevalence increased with exposure in areas where malaria was or was not endemic. a marked isotype switch to cytophilic (immunoglobulin g1 [igg1]/igg3) antibodies was evident with increasing exposure exclusively in residents from areas of endemicity. | 2006 | 16369044 |
| low autochtonous urban malaria in antananarivo (madagascar). | the study of urban malaria is an area undergoing rapid expansion, after many years of neglect. the problem of over-diagnosis of malaria, especially in low transmission settings including urban areas, is also receiving deserved attention. the primary objective of the present study was to assess the frequency of malaria among febrile outpatients seen in private and public primary care facilities of antananarivo. the second aim was to determine, among the diagnosed malaria cases, the contribution o ... | 2006 | 16573843 |
| anopheles culicifacies sibling species b and e in sri lanka differ in longevity and in their susceptibility to malaria parasite infection and common insecticides. | members of the anopheles culicifacies giles complex (diptera: culicidae) are well established as the predominant vectors of malaria in sri lanka. until recently, only sibling species b was reported to be present in sri lanka, which was surprising as species b is a poor vector of malaria in india. this was clarified by the identification through y-chromosome morphology that what was reported as b on the island is really a mixture of b and e. the fecundity, longevity and insecticide resistance of ... | 2006 | 16608500 |
| multi-character population study of the vir subtelomeric multigene superfamily of plasmodium vivax, a major human malaria parasite. | plasmodium vivax, the most widely distributed human malaria parasite, contains the subtelomeric multigene vir superfamily corresponding to circa 10% of its coding genome. in this work, we used a multi-character strategy to study the vir gene repertoire circulating in natural parasite populations obtained directly from 32 human patients from endemic regions of brazil and sri lanka. cladistic analysis confirmed the existence of vir subfamilies, which varied in size and allele polymorphisms. moreov ... | 2006 | 16730808 |
| moderate transmission but high prevalence of malaria in madagascar. | malaria transmission remains poorly documented in areas of low transmission. a study has been carried out over two consecutive years in analamiranga, a village located at an altitude of 885m on the western edge of the malagasy highlands, with the aim of generating and updating malariometric indexes for both mosquitoes and schoolchildren. in this village, no vector control measures were performed during the study period nor during previous decades. mosquitoes were collected monthly when landing o ... | 2006 | 16842796 |
| comparison of naturally acquired antibody responses against the c-terminal processing products of plasmodium vivax merozoite surface protein-1 under low transmission and unstable malaria conditions in sri lanka. | we report here, for the first time, a comparison of naturally acquired antibody responses to the 42 and 19 kda c-terminal processing products of plasmodium vivax merozoite surface protein-1 assayed by elisa using p42 and p19 baculovirus-derived recombinant proteins, respectively. test populations comprised patients with microscopy confirmed acute p. vivax infections from two regions endemic for vivax malaria where low transmission and unstable malaria conditions prevail, and a non-endemic urban ... | 2007 | 17055511 |
| genetic diversity and selection at the plasmodium vivax apical membrane antigen-1 (pvama-1) locus in a sri lankan population. | plasmodium vivax apical membrane antigen 1 (pvama-1) is an important malaria vaccine candidate. we present the first comprehensive analysis of nucleotide diversity across the entire pvama-1 gene using a single population sample from sri lanka. in contrast to what has been observed at the ama-1 locus of plasmodium falciparum, the signature of diversifying selection is seen most strongly in domain ii of pvama-1, indicating that the different domains in each species may be subject to varying select ... | 2007 | 17244598 |
| island-wide diversity in single nucleotide polymorphisms of the plasmodium vivax dihydrofolate reductase and dihydropteroate synthetase genes in sri lanka. | single nucleotide polymorphisms (snps) in the plasmodium vivax dihydrofolate reductase (pfdhfr) and dihydropteroate synthetase (pvdhps) genes cause parasite resistance to the antifolate drug combination, sulphadoxine/pyrimethamine (sp). monitoring these snps provide insights into the level of drug pressure caused by sp use and presumably other antifolate drugs. in sri lanka, chloroquine (cq) with primaquine (pq) and sp with pq is used as first and second line treatment, respectively, against unc ... | 2007 | 17349045 |
| longitudinal survey of malaria morbidity over 10 years in saharevo (madagascar): further lessons for strengthening malaria control. | madagascar has been known for having bio-geo-ecological diversity which is reflected by a complex malaria epidemiology ranging from hyperendemic to malaria-free areas. malaria-related attacks and infection are frequently recorded both in children and adults living in areas of low malaria transmission. to integrate this variability in the national malaria control policy, extensive epidemiological studies are required to up-date previous records and adjust strategies. | 2009 | 19660116 |
| interaction of malaria with a common form of severe thalassemia in an asian population. | in many asian populations, the commonest form of severe thalassemia results from the coinheritance of hbe and beta thalassemia. the management of this disease is particularly difficult because of its extreme clinical diversity; although some genetic and adaptive factors have been identified as phenotypic modifiers, the reasons remain unclear. because the role of the environment in the course of severe thalassemia has been neglected completely and because malaria due to both plasmodium falciparum ... | 2009 | 19841268 |
| pre-elimination stage of malaria in sri lanka: assessing the level of hidden parasites in the population. | with the dramatic drop in the transmission of malaria in sri lanka in recent years, the country entered the malaria pre-elimination stage in 2008. assessing the community prevalence of hidden malaria parasites following several years of extremely low transmission is central to the process of complete elimination. the existence of a parasite reservoir in a population free from clinical manifestations, would influence the strategy for surveillance and control towards complete elimination. | 2010 | 20089157 |
| geographic structure of plasmodium vivax: microsatellite analysis of parasite populations from sri lanka, myanmar, and ethiopia. | genetic diversity and population structure of plasmodium vivax parasites can predict the origin and spread of novel variants within a population enabling population specific malaria control measures. we analyzed the genetic diversity and population structure of 425 p. vivax isolates from sri lanka, myanmar, and ethiopia using 12 trinucleotide and tetranucleotide microsatellite markers. all three parasite populations were highly polymorphic with 3-44 alleles per locus. approximately 65% were mult ... | 2010 | 20133999 |
| plasmodium vivax clinical malaria is commonly observed in duffy-negative malagasy people. | malaria therapy, experimental, and epidemiological studies have shown that erythrocyte duffy blood group-negative people, largely of african ancestry, are resistant to erythrocyte plasmodium vivax infection. these findings established a paradigm that the duffy antigen is required for p. vivax erythrocyte invasion. p. vivax is endemic in madagascar, where admixture of duffy-negative and duffy-positive populations of diverse ethnic backgrounds has occurred over 2 millennia. there, we investigated ... | 2010 | 20231434 |
| genetic complexity of plasmodium vivax infections in sri lanka, as reflected at the merozoite-surface-protein-3alpha locus. | the presence of genetically different strains of malarial parasites in cases of human malaria is a severe drawback in the successful control of the disease. in sri lanka, although this species accounts for 60%-80% of all of the cases of clinical malaria that occur each year, the genetic complexity of plasmodium vivax on the island remains to be elucidated. in recent studies based on pcr-rflp and the parasites' merozoite-surface-protein-3alpha locus, the genetic structure of 201 clinical isolates ... | 2010 | 20406577 |
| [malaria cases diagnosed at the parasitology department of the joseph-ravoahangy-andrianavalona university hospital centre, antananarivo, madagascar, 2005-2008]. | | 2010 | 20525547 |
| plasmodium vivax and the duffy antigen: a paradigm revisited. | the duffy blood group antigen is the portal of entry of the plasmodiumvivax malaria parasite into human red blood cells and the receptor for a number of cxc and cc chemokines. we review here epidemiological data and evidence derived from therapeutic or experimental human infections associating p. vivax and the duffy glycoprotein and laboratory studies indicating that p. vivax uses the duffy antigen as a receptor to invade the red cell. we then review recent field observations indicating that the ... | 2010 | 20655790 |
| genetic diversity and recombination at the c-terminal fragment of the merozoite surface protein-1 of plasmodium vivax (pvmsp-1) in sri lanka. | extensive polymorphism in the genes encoding for surface antigens of plasmodium falciparum and plasmodium vivax has been a serious impediment for malaria vaccine development. one such antigen is the merozoite surface protein-1 (msp-1). the msp-1 precursor after proteolytic cleavage generates a c-terminal fragment of 42 kda (msp-1(42)), which subsequently produces 33 kda (msp-1(33)) and 19 kda (msp-1(19)) fragments. since msp-1(42) is currently being considered as a candidate for vaccine developm ... | 2010 | 20933611 |
| genetic diversity of plasmodium vivax duffy binding protein ii (pvdbpii) under unstable transmission and low intensity malaria in sri lanka. | elucidating the genetic diversity of the duffy binding protein ii (pvdbpii), a leading vaccine candidate for vivax malaria, in different geographical settings is vital. in sri lanka malaria transmission is unstable with low intensity. a relatively high level of allelic diversity, with 27 polymorphic nucleotides and 33 (aa) haplotypes was detected among the pvdbpii gene in 100 local plasmodium vivax isolates collected from two hypoendemic areas, and from a non endemic area of the country. mutatio ... | 2011 | 21554998 |
| evaluation of the genetic diversity of domain ii of plasmodium vivax apical membrane antigen 1 (pvama-1) and the ensuing strain-specific immune responses in patients from sri lanka. | antigenic polymorphism displayed by malaria parasites is a skewed schema to escape the host immune system. the prevailing genetic diversity at domain ii of the plasmodium vivax apical membrane antigen-1 (pvama-1dii) was characterized in 64 single clone p. vivax isolates from sri lanka, where unstable malaria prevails with low intensity. in sri lanka, the pvama-1dii gene showed meager meiotic recombination with the enclosure of single nucleotide polymorphisms (snps). eleven amino acid (a.a.) vari ... | 2011 | 21784116 |
| reduced impact of pyrimethamine drug pressure on plasmodium malariae dihydrofolate reductase gene. | molecular investigations performed following the emergence of sulfadoxine-pyrimethamine (sp) resistance in plasmodium falciparum have allowed the identification of the dihydrofolate reductase (dhfr) enzyme as the target of pyrimethamine. although clinical cases of plasmodium malariae are not usually treated with antifolate therapy, incorrect diagnosis and the high frequency of undetected mixed infections has probably exposed non-p. falciparum parasites to antifolate therapy in many areas. in thi ... | 2011 | 22123682 |
| analysis of polymorphisms in the merozoite surface protein-3α gene and two microsatellite loci in sri lankan plasmodium vivax: evidence of population substructure in sri lanka. | the geographical distribution of genetic variation in plasmodium vivax samples (n = 386) from nine districts across sri lanka is described using three markers; the p. vivax merozoite surface protein-3α (pvmsp-3α) gene, and the two microsatellites m1501 and m3502. at pvmsp-3α, 11 alleles were found with an expected heterozygosity (h(e)) of 0.81, whereas at m1501 and m3502, 24 alleles (h(e) = 0.85) and 8 alleles (h(e) = 0.74) were detected, respectively. overall, 95 unique three locus genotypes we ... | 2011 | 22144433 |
| the origins of african plasmodium vivax; insights from mitochondrial genome sequencing. | plasmodium vivax, the second most prevalent of the human malaria parasites, is estimated to affect 75 million people annually. it is very rare, however, in west and central africa, due to the high prevalence of the duffy negative phenotype in the human population. due to its rarity in africa, previous studies on the phylogeny of world-wide p. vivax have suffered from insufficient samples of african parasites. here we compare the mitochondrial sequence diversity of parasites from africa with thos ... | 2011 | 22195007 |
| country-wide assessment of the genetic polymorphism in plasmodium falciparum and plasmodium vivax antigens detected with rapid diagnostic tests for malaria. | rapid diagnostic tests (rdts) are becoming increasingly indispensable in malaria management, as a means of increasing the accuracy of diagnosis. the who has issued recommendations, but the selection of the most suitable rdt remains difficult for users in endemic countries. the genetic variability of the antigens detected with rdts has been little studied, but may affect the sensitivity of rdts. this factor has been studied by comparisons between countries at continental level, but little informa ... | 2008 | 18957099 |