Impact of Seasonal Malaria Chemoprevention on Immunity Against Malaria Among Children in Northern...
Plasmodium Malariae InfectionSMC1 moreThis study aims to evaluate the effects of SMC (Seasonal malaria chemoprevention) with Sulfadoxine-Pyrimethamine (SP) and Amodiaquine (AQ) on the evolution of anti-malarial immunity of children and their susceptibility to malarial infection. This is a cross-sectional study on children aged 6 to 59 months with/without SMC in two villages in northern Benin. Sociodemographic and clinical data as well as repeated blood samples will be collected from 440 children (before, during and after treatment). Samples will be analyzed using a Luminex assay to investigate antibody responses to MSP (merozoite surface protein) , Glurp (Glutamate-Rich Protein) and a panel of PfEMP1. qPCR (quantitative polymerase chain reaction) will be used to detect the prevalence of malaria at this period and parasites infecting children will be characterize during the follow up.
Artemisinin-resistant Malaria in Cambodia
Plasmodium Falciparum MalariaBackground: - Artemisinin-based combination therapies (ACTs) are the first-line treatments for malaria. ACTs are highly effective, but malaria caused by the Plasmodium falciparum parasite is becoming resistant to some ACTs. ACT-resistant malaria has shown up in some parts of Cambodia, but not yet in other parts of the country. This has been shown by treating patients with ACTs, checking the amount of parasites in the patient s blood every 6 hours, and calculating the rate of parasite clearance. The parasite clearance rate in response to ACTs is getting slower in western Cambodia and may be the first sign of ACT resistance. Researchers want to study how effective ACTs are in different regions of Cambodia. This study will look at the extent of ACT resistance and how widespread ACT-resistant malaria has become. Objectives: - To compare the prevalence of ACT-resistant malaria in western, northern and eastern Cambodia. Eligibility: - Individuals between 2 and 65 years of age who have uncomplicated Plasmodium falciparum malaria and have not taken any antimalarial drugs for their symptoms in the previous 7 days. Design: Participants will be recruited from clinics and hospitals in three Cambodian provinces. Participants will be informed about the study and their consent to participate in the study will be obtained. A venous blood sample will be obtained from patients before treatment and used for laboratory experiments to measure parasite and patient factors that might affect the parasite clearance rate. Participants with malaria will be treated with dihydroartemisinin-piperaquine (DHA-PPQ), the standard first-line treatment for malaria in Cambodia. Treatment will be monitored with frequent blood samples obtained from a finger prick. The amount of malaria parasites in each blood sample will be counted and followed until they are no longer detectable. Participants will have weekly follow-up visits for up to 9 weeks. Finger-prick blood samples will be taken at each visit to see if the parasites reappear after treatment with ACT.
Re-exposure of Human Volunteers to a Heterologous Strain of P. Falciparum Sporozoites
MalariaFalciparumIn a previous study (NL33904.091.10) the investigators challenged 24 volunteers after Chloroquine Prophylaxis Sporozoites (CPS) immunization with 45, 30 or 15 infected mosquito-bites respectively. The availability of this immunized cohort opens the unique opportunity to determine protection to a heterologous challenge for both of the protected and unprotected volunteers as the previous challenge infection might have served as immunological boost to the unprotected volunteers. In the current observational, proof of principle study, the investigators aim to investigate the protection on an individual basis of these previously immunized and challenged volunteers against a heterologous P. falciparum challenge.
Impact of Insecticide Resistance on Vector Control
MalariaFalciparumThe purpose of the study is to determine whether long lasting insecticidal nets and indoor residual insecticide spraying, alone or in combination, are effective for controlling insecticide resistant anopheles mosquitoes for malaria prevention.
Malaria Transmission Studies in Mali
MalariaFalciparumBackground: - Malaria is an illness caused by a parasite spread by mosquitoes. When a mosquito bites a person who is infected with a kind of parasite called a gametocyte, it is able to spread the infection to another person. Not everyone infected with parasites have gametocytes in their blood. As a result, not everyone can spread malaria to others. Researchers are interested in learning more about why some healthy people have gametocytes in their blood and others do not. Identifying the people who have gametocytes in their blood can help target treatment and reduce the spread of malaria. This study will focus on the people of the village of Kenieroba in Mali, where malaria is common. Objectives: - To study the relationship between gametocytes and malaria transmission in Mali. Eligibility: - Individuals between 6 months and 65 years of age who live in Kenieroba, Mali, and will stay in the area for 1 year. Design: For 1 year, participants will have study visits once every 2 weeks (twice a month, for a total of 24 visits). The visits will last 30 minutes each. At each visit, participants will provide a small blood sample. They will report any symptoms of malaria such as fever, headache, and body aches. Participants will be encouraged to seek medical treatment if they experience malaria symptoms between visits. Participants who have malaria symptoms will have a blood test for malaria parasites. Those who have parasites in the blood will receive antimalarial treatment. Three times over 1 year, a larger blood sample will be collected. These blood samples will be taken once in the dry season, once in the wet season, and once in the next dry season. Women between 14 and 45 years of age will also provide urine samples to test for pregnancy. Pregnant women will not be asked to give blood samples.
Iron Absorption and Utilization in Adolescents Infected With Malaria Parasites, Hookworms or Schistosoma...
MalariaFalciparum2 moreThe aim of this study is to investigate the change in iron metabolism in relation to malaria and helminth infections using a stable isotope technique.
ACT for the Home Management in Malagasy Children
FeverSuspected MalariaThe purpose of this study is to assess the feasibility, the acceptability and the effectiveness of the use of the Artesunate + Amodiaquine Fixed Dose Combination for the home management of presumed malaria in Malagasy children by the community-based service providers.
Innate and Acquired Resistance to Plasmodium Falciparum Malaria in Mali
MalariaThis study, sponsored by NIAID and the University of Bamako, Mali, will identify genetic and other factors that may protect against severe malaria in some children. Children between 6 months and 17 years of age who live in Kenieroba, Fourda or Bozokin villages in Mali may enroll in the study. Participants have a blood sample collected by finger prick with a small needle. The blood is examined for gene variants that influence the severity of disease in children exposed to the malaria parasite. Children who develop a fever or other symptoms of malaria are evaluated and treated in Kenieroba s health center for up to 5 years from entering the study, or until they reach 18 years of age. The children are treated with artesunate and amodiaquine. Children with severe disease are treated with quinine. One tablespoon of blood is drawn from the children for study. At the end of the dry season and the wet season, a subset of 200 healthy children are asked to provide 1 or 2 tablespoons of blood, drawn through a needle placed in a vein in the arm. Additional research blood samples may be requested from children between 2 and 17 years old. Blood will not be taken from any child more than twice a year. ...
Evaluation of Volume Status, Haemodynamics and Microcirculatory Flow in Adult Patients With Severe...
Severe Falciparum Malariaacidosis, acute renal failure and acute pulmonary oedema are common, and frequently fatal, manifestations of severe P. falciparum malaria. The course of all three might be ameliorated by optimising a patient's intravenous fluid therapy. The fluid treatment of severe malaria is presently empirical, by defining cardiovascular responses to volume replacement we would provide a physiological basis for resuscitation strategies. We will use pulse contour cardiac output monitoring (PiCCOTM) to guide the fluid resuscitation of patients admitted to intensive care with severe malaria. With data collected during the patients' admission we hope to: Assess the degree of hypovolaemia in adults with severe malaria and its contribution to microcirculatory dysfunction and acidosis. To assess the relationships between volume status, haemodynamic parameters and the renal and pulmonary manifestations of severe malaria. To assess the utility of central venous pressure measurement as a guide for fluid administration in patients with severe malaria To investigate the prognostic and clinical utility of central venous oxygen saturation in severe malaria In this way we hope to develop a greater understanding of the pathophysiology of haemodynamic derangement in severe malaria. By comparing the PiCCO derived data with simpler clinical parameters, we hope to determine potential fluid resuscitation strategies - relevant for a resource poor setting - whose efficacy could be confirmed in future trials.
Impact of IPT With Sulfadoxin Pyrimetamin on Pregnant Women and Their Babies Outcomes in Peri-urban...
MalariaPregnancyThe purpose of this is to determine the impact of intermittent preventive treatment (IPT) with sulfadoxine-pyrimethamine (SP) on the morbidities associated with malaria in pregnant women and newborns in rural peri-urban areas of Bobo-Dioulasso, 5 years after its implemented.