Increased circulation time of Plasmodium falciparum underlies persistent asymptomatic infection in the dry season.

The dry season is a major challenge for Plasmodium falciparum parasites in many malaria endemic regions, where water availability limits mosquito vectors to only part of the year. How P. falciparum bridges two transmission seasons months apart, without being cleared by the human host or compromising host survival, is poorly understood.

A panel of recombinant proteins from human-infective Plasmodium species for serological surveillance.

Background: Malaria remains a global health problem and accurate surveillance of Plasmodium parasites that are responsible for this disease is required to guide the most effective distribution of control measures. Serological surveillance will be particularly important in areas of low or periodic transmission because patient antibody responses can provide a measure of historical exposure. While methods for detecting host antibody responses to Plasmodium falciparum and Plasmodium vivax are well established, development of serological assays for Plasmodium knowlesi, Plasmodium ovale and Plasmodium malariae have been inhibited by a lack of immunodiagnostic candidates due to the limited availability of genomic information.

Multiplicity of Asymptomatic Plasmodium falciparum Infections and Risk of Clinical Malaria: A Systematic Review and Pooled Analysis of Individual Participant Data.

Background: The malaria parasite Plasmodium falciparum holds an extensive genetic polymorphism. In this pooled analysis, we investigate how the multiplicity in asymptomatic P. falciparum infections-that is, the number of coinfecting clones-affects the subsequent risk of clinical malaria in populations living under different levels of transmission.

Persistent transmission of Plasmodium malariae and Plasmodium ovale species in an area of declining Plasmodium falciparum transmission in eastern Tanzania.

A reduction in the global burden of malaria over the past two decades has encouraged efforts for regional malaria elimination. Despite the need to target all Plasmodium species, current focus is mainly directed towards Plasmodium falciparum, and to a lesser extent P. vivax.

Cellular aging dynamics after acute malaria infection: A 12-month longitudinal study.

Accelerated cellular aging and reduced lifespan have recently been shown in birds chronically infected with malaria parasites. Whether malaria infection also affects cellular aging in humans has not been reported. Here, we assessed the effect of a single acute Plasmodium falciparum malaria infection on cellular aging dynamics in travelers prospectively followed over one year in Sweden.

Detection of Malaria Parasites After Treatment in Travelers: A 12-months Longitudinal Study and Statistical Modelling Analysis.

The rapid clearance of malaria parasite DNA from circulation has widely been accepted as a fact without being systemically investigated. We assessed the persistence of parasite DNA in travelers treated for Plasmodium falciparum malaria in a malaria-free area. Venous blood was collected at the time of admission and prospectively up to one year.

Major transcriptional changes observed in the Fulani, an ethnic group less susceptible to malaria.

The Fulani ethnic group has relatively better protection from malaria, as reflected by fewer symptomatic cases of malaria, lower infection rates, and lower parasite densities compared to sympatric ethnic groups. However, the basis for this lower susceptibility to malaria by the Fulani is unknown. The incidence of classic malaria resistance genes are lower in the Fulani than in other sympatric ethnic populations, and targeted SNP analyses of other candidate genes involved in the immune response to malaria have not been able to account for the observed difference in the Fulani susceptibility to Therefore, we have performed a pilot study to examine global transcription and DNA methylation patterns in specific immune cell populations in the Fulani to elucidate the mechanisms that confer the lower susceptibility to malaria.

Treatment of Chronic Asymptomatic Plasmodium falciparum Infection Does Not Increase the Risk of Clinical Malaria Upon Reinfection.

Background: Chronic asymptomatic Plasmodium falciparum infections are common in endemic areas and are thought to contribute to the maintenance of malaria immunity. Whether treatment of these infections increases the subsequent risk of clinical episodes of malaria is unclear.

Methods: In a 3-year study in Mali, asymptomatic individuals with or without P.

High Rate of Treatment Failures in Nonimmune Travelers Treated With Artemether-Lumefantrine for Uncomplicated Plasmodium falciparum Malaria in Sweden: Retrospective Comparative Analysis of Effectiveness and Case Series.

Background: Artemisinin-based combination therapy (ACT) is the first-line treatment of Plasmodium falciparum malaria. Since the introduction of artemether-lumefantrine (AL) for treatment of uncomplicated malaria in Sweden, treatment failures have been reported in adults.

Methods: A retrospective comparative analysis of treatment regimen for P.

Oil-Fortified Maize Porridge Increases Absorption of Lumefantrine in Children with Uncomplicated Falciparum Malaria.

Artemether-lumefantrine (AL) is a first-line treatment for uncomplicated malaria. Absorption of lumefantrine (LUM) is fat dependent, and in children, intake is recommended with milk. We investigated whether oil-fortified maize porridge can be an alternative when milk is not available.

Improved ex vivo blood compatibility of central venous catheter with noble metal alloy coating.

Central line associated bloodstream infections (CLABSIs) are a serious cause of morbidity and mortality induced by the use of central venous catheters (CVCs). Nobel metal alloy (NMA) coating is an advanced surface modification that prevents microbial adhesion and growth on catheters and thereby reduces the risk of infection. In vitro microbiological analyses have shown up to 90% reduction in microbial adhesion on coated CVC compared to uncoated ones.

Asymptomatic Multiclonal Plasmodium falciparum Infections Carried Through the Dry Season Predict Protection Against Subsequent Clinical Malaria.

Background: Immunity to the antigenically diverse parasite Plasmodium falciparum is acquired gradually after repeated exposure. Studies in areas of high malaria transmission have shown that asymptomatic individuals infected with multiclonal infections are at reduced risk of febrile malaria during follow-up.

Methods: We assessed the relationship between the genetic diversity of clones in P.

Epidemiology of malaria in a village in the Rufiji River Delta, Tanzania: declining transmission over 25 years revealed by different parasitological metrics.

Background: Assessments of the epidemiology of malaria over time are needed to understand changes in transmission and guide control and elimination strategies.

Methods: A longitudinal population study was established in 1985 in Nyamisati village in the Rufiji River Delta, Tanzania. A physician and research team lived in the village 1984-2000.

Cytokine gene haplotypes with a potential effect on susceptibility to malaria in sympatric ethnic groups in Mali.

Cytokines are important players in the immune responses, and an unbalance in pro- and anti-inflammatory cytokine responses may affect parasitemia and pathology in a Plasmodium falciparum infection. Polymorphisms in cytokine genes may affect not only the levels of the protein, but many down-stream functions, such as production of C-reactive protein and immunoglobulin isotype switching. Susceptibility to malaria has been shown to differ between individuals with different genetic backgrounds, as indicated by studies in Fulani and non-Fulani ethnic groups.

Marked differences in CRP genotype frequencies between the Fulani and sympatric ethnic groups in Africa.

Background: C-reactive protein (CRP) is an acute phase protein that can activate various immune cells and bind to certain Fcgamma receptors. The latter may compete with the binding of IgG antibodies to these receptors and could thereby interfere with the antigen-specific immune response. Polymorphisms in the promoter region of the CRP gene have been strongly associated with the plasma concentration of CRP.