Active clinical trials for "Malaria"

Background: - 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.

In 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.

The 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.

Background: - 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.

Background: - Malaria is a disease that affects many people in Mali and in Africa. It is caused by germs that are spread by mosquito bites. Researchers are creating vaccines that they hope will prevent malaria infection and/or the spread of it. Objective: - To test if the PfSPZ vaccine can stop malaria spread by mosquitoes. Eligibility: - People currently enrolled in the ongoing PfSPZ malaria vaccine trial. Participants must be willing to have uninfected mosquitoes bite them. Design: Participants will be able to take part in this study at every visit after receiving all scheduled vaccinations. Participants will be asked whether they are willing to participate in the procedures. Female participants will have a pregnancy test. Researchers will put about 60 mosquitoes in 2 or 3 cups (20 or 30 in each cup). They will hold each cup to the participant s leg or arm so the mosquitoes can bite. These mosquitoes do not carry germs and will take about 3 drops of blood total. Participants will get a cream for any swelling or itching. Participants will be checked the next day for any discomfort. Participants may take part in this feeding test multiple times, if they are willing. If participants have malaria parasites in their blood, they may be asked to take part in another study. For this, they will sleep alone in their hut the night after the feeding test. A study team will set up nets to collect mosquitoes that may have bitten the participant overnight.

The 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.

This study will be the first time that the candidate malaria vaccine Apical Membrane Antigen 1 (PfAMA-1-FVO[25-545]) will be tested in malaria endemic populations. The phase Ib study will include adults who will be randomly allocated to either receive the malaria vaccine or the vaccine against Tetanus. Each participant will receive 3 immunizations, without the clinical investigators or the participants themselves knowing what has been given. They will then be follow-up up for immediate reactions to vaccination, and also over a longer term of one year. Blood will be taken to evaluate the biological safety parameters and also immune responses.

The study aims to show that the candidate malaria vaccine GMZ2 is as safe as the already publicly used vaccine against rabies. 40 adult male Gabonese volunteers will be enrolled and randomly allocated to receive either malaria vaccine or rabies vaccine without the investigator or the participants knowing what they received. They will receive 3 doses each at one month intervals, and will be followed up for one year to evaluate safety parameters. This is the first time this product will be tested in Africa

This study will determine the immune response to malaria infection in healthy volunteers compared with malaria patients. Malaria affects millions of people in Mali and Africa. It can cause fever, headaches, body aches, and weakness. Without treatment, the disease can be very serious in children. Developing an effective vaccine against the parasite that causes malaria is a crucial step toward controlling the disease; however, vaccines tested so far have provided very short-lived protection. A better understanding of the natural immunity to malaria may provide insight that can be applied to developing a more effective vaccine. People 18 years of age or older who live in Kambila, Tieneguebougou or Kalifabougou, Mali, and are in good health may be eligible for this study. Participants undergo a complete physical examination at the start of the study and then once a year for the 4-year duration of the study. They have a maximum of nine clinic visits a year to collect blood samples for research. The visits last about one hour, including a 30-minute observation time after the blood draw.

The 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.