C Drakeley

..abstract:..

..The development and establishment of quality systems was a requirement for trial conduct to meet international regulatory standards, as well as providing an important capacity strengthening opportunity for study centres...

..75 mg/kg) on malaria transmission was determined in an area of very low and seasonal malaria transmission in northern Tanzania...

..In this study, antibodies to Plasmodium falciparum merozoite antigens were compared between blood and saliva samples from the same individuals in unlinked surveys conducted in Tanzania and The Gambia...

..In the surveyed area of rural southern Tanzania, bed net use steadily increased over the last decade, reducing malaria transmission intensity by 94%...

..Malaria transmission depends on the presence of gametocytes in the peripheral blood. In this study, the age-dependency of gametocytaemia was examined by microscopy and molecular tools...

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..The size of this effect is estimated in symptomatic P. falciparum infections...

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..In this study, data on meteorological, demographic, entomological and parasitological data over the course of a year was collected to describe malaria epidemiology in a single village of low transmission intensity...

..Although recommendations for the storage and analysis of small molecule analytes in blood spots exist, there are no published systematic studies of the stability of antibodies under different storage conditions...

..The relationship between the burden of uncomplicated malaria and transmission intensity is unclear and a better understanding of this relationship is important for the implementation of intervention programmes...

..The current paper seeks a procedure which avoids the disadvantages of these current options and whose parameter values are more clearly justified...

..Phase III trials of the malaria vaccine, RTS, S, are now underway across multiple sites of varying transmission intensity in Africa. Heterogeneity in exposure, vaccine response and waning of efficacy may bias estimates of vaccine efficacy...

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..This study identified factors that influence gametocytaemia in asymptomatic children in the absence and presence of pyrimethamine-sulphadoxine (SP) antimalarial treatment...

..The aim of this study was to identify and compare factors associated with Plasmodium falciparum gametocyte carriage in three regions of differing malaria endemicity...

..Simple mathematical models were fitted to data from clinical trials in order to determine the mean gametocyte circulation time and duration of gametocyte carriage in treated malaria patients...

..RDTs are now widely used for the diagnosis of malaria and estimation of parasite rates, and this method represents a further use for these devices in malaria control...

..This study aimed to explore why malaria slides are requested and how their results guide treatment decisions in an area of low transmission of P. falciparum...

..This study describes diagnostic and treatment practices in Mto wa Mbu, an area that used to be hyperendemic for malaria, but where no recent assessments of transmission intensity have been conducted...

..This study explores the determinants of uptake for both ITNs and IPTp-SP by pregnant women and the role that individual knowledge and socio-economic status has to play for each...

..The validity of this conversion in malaria endemic settings was assessed...

..Knockdown resistance (kdr) confers resistance to the pyrethroid class of insecticides with cross-resistance to DDT through single nucleotide polymorphisms (SNPs) in the voltage-gated sodium channel gene...

..There has been very limited investigation of the ecology of vectors during the dry season, when numbers are very limited and distributions may be restricted...

..This study aims to provide parasite prevalence data from three sites in the Gambia and Guinea Bissau, respectively, and compares the usefulness of PCR, rapid diagnostic tests (RDT), serology and slide-microscopy for surveillance...

..These results suggest that effective malaria transmission-reducing antibodies do not commonly circulate in African children, and that recent gametocyte carriage is required to initiate and/or boost such responses...

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..Behavioural adaptation by mosquitoes to increasing ITN coverage could allow vector mosquitoes to bite outside of peak sleeping hours and undermine efficacy of this key malaria prevention measure...

..falciparum parasite carriage and antibody responses to the asexual stage antigens, G6PD deficiency and alpha+-thalassaemia in 464 subjects from a low endemic area in northern Tanzania...

..Control measures aimed at reduction of transmission may have only a limited effect in areas of moderate seasonal transmission if directed only at children...

..This may be due to decreased exposure to gametocytes, probably as a result of increased asexual and/or gametocyte specific immunity...

..Here, we review data on gametocyte carriage in the context of the development of naturally acquired immunity and population infectivity...

..Estimates based on entomological factors lack precision and are not cost-effective to obtain. We tested altitude and rainfall measurements as correlates of transmission intensity in different ecological settings...

..This may be caused by variation in sexual stage antigens and/or alternative modes of transmission-blocking immunity, both of which have implications for vaccine implementation...

..We assessed the effect on Plasmodium falciparum transmissibility of the addition of AS to chloroquine (CQ) in an area of The Gambia where resistance to CQ is increasing...

..Here we review what is known and what new evidence is needed to maximise the utility of RDTs in Africa...

..These estimates show large variations over short distances in time and space. They are all markedly lower than those reported from nearby rural areas and for other parts of Tanzania...

..The WHO-packaged six-dose regimen of artemether-lumefantrine is effective taken unsupervised, although cost is a major limitation...

..Artesunate reduced posttreatment infectivity dramatically but did not abolish it completely. The study raises questions about any policy to use pyrimethamine-sulfadoxine alone as the first-line treatment for malaria...

..016). Serologic markers are a promising tool for detecting spatial variation in malaria exposure and evaluating malaria control efforts in areas where transmission has decreased to levels below the detection limit of microscopy...

..This study set out to determine the efficacy and safety of several antimalarial drugs and combinations in pregnant women with uncomplicated malaria...

..Here we present a suggested methodology, highlight the advantages and shortcomings of serological measurements of malaria transmission and identify areas in which further work is desirable...

..This study evaluated SCR generated from samples collected from health facility attendees as a tool for a rapid assessment of malaria transmission intensity...

..Here we present a review of the historical data and use it to assess the serological contribution to monitoring malaria elimination...

..The triple-dhfr/double-dhps genotype is present in all three regions with frequencies ranging between 30 and 63%, indicating that treatment failure rates are likely to be high...

..Resistance to sulfadoxine-pyrimethamine is now increasing, especially in southeast Africa...

..To study the diagnosis and outcomes in people admitted to hospital with a diagnosis of severe malaria in areas with differing intensities of malaria transmission...

..An understanding of the relationships among the level of exposure to Plasmodium falciparum, age, and severity of malaria can provide evidence of whether this is likely...

..This heterogeneity creates opportunities for targeted interventions but only if hot spots of malaria transmission can be easily identified...

..To compare rapid diagnostic tests (RDTs) for malaria with routine microscopy in guiding treatment decisions for febrile patients...

..These components are drawn together to show how control measures that aim to reduce malaria transmission, such as mass drug administration and a transmission-blocking vaccine, might better be deployed...

..Understanding the effector mechanisms underlying these two immune functions will assist in the design of transmission-reducing interventions against malaria...

..Our data also throw light on the consequences of class switch decisions on the gradual acquisition of antimalarial immunity...

..Chloroquine plus artesunate is not sufficiently efficacious to justify its introduction as a replacement for chloroquine monotherapy in The Gambia...

..In contrast, few studies have examined the surface of the gametocyte-infected erythrocyte...

..Observations in natural Plasmodium falciparum populations after removal of failing drugs suggest that there is a fitness cost of drug resistance...

..Thus, drug combinations must be identified which minimise gametocyte emergence in treated cases, and so prevent selective transmission of parasites resistant to any of the partner drugs...

..This fall appears to have started before the widespread introduction of insecticide-treated nets. In the new era of calls to eliminate and eradicate malaria in sub-Saharan Africa, exploring possible causes for this fall seem pertinent...