Objective The development of naturally acquired immunity (NAI) against Plasmodium falciparum malaria is poorly understood. Previous studies of continuous and intermittent chemoprophylaxis in infants have provided evidence that the age of first exposure to P. falciparum during infancy may be important in determining the development of NAI, as measured by incidence of clinical malaria during the second year of life. These studies suggest that exposure to P. falciparum prior to 5 months of age does not result in the development of NAI, while exposure to P. falciparum after 5 months of age leads to development of NAI. The overall objective is to evaluate the effect of exposure to P. falciparum erythrocytic stage antigens during different periods of infancy on the development of NAI. In order to explore the effect of age in the build-up of NAI we have designed a 3-arm randomized double-blind placebo-controlled trial in an endemic area of southern Mozambique in which we selectively control exposure to P. falciparum at different periods during infancy (2.5-5.5 months, 5.5-10.5 months or none) with monthly chemoprophylaxis with Sulphadoxine-Pyrimethamine+Artesunate. Infants will be enrolled at birth or when aged less than 2 months from HIV-negative women and allocated to one of three cohorts of 98 children each. Participants will be followed up by active and passive case detection until 11 months of age and by passive case detection from 11 to 24 months. Five cross-sectional surveys will be conducted to obtain blood samples. The risk of clinical malaria and anaemia during the second year of life will be compared between cohorts, as well as its correlation with the type and quality of immune responses (antibodies to several P. falciparum antigens, cytokines), oxidative stress markers and host genetic factors. These results should shed light on the determinants of the development of anti-P. falciparum responses early in life and the potential constraints to early life immunisation. Fields of science medical and health scienceshealth sciencesinfectious diseasesmalarianatural sciencesbiological sciencesgeneticsmedical and health scienceshealth sciencespublic healthmedical and health sciencesbasic medicineimmunologyimmunisationmedical and health sciencesbasic medicinepharmacology and pharmacypharmaceutical drugsvaccines Programme(s) FP6-LIFESCIHEALTH - Life sciences, genomics and biotechnology for health: Thematic Priority 1 under the Focusing and Integrating Community Research programme 2002-2006. Topic(s) LSH-2004-2.3.0-5 - Neonatal immunity Call for proposal FP6-2004-LIFESCIHEALTH-5 See other projects for this call Funding Scheme STREP - Specific Targeted Research Project Coordinator INSTITUT D'INVESTIGACIONS BIOMÈDIQUES AUGUST PI I SUNYER EU contribution No data Address Villarroel 170 BARCELONA Spain See on map Links Website Opens in new window Total cost No data Participants (6) Sort alphabetically Sort by EU Contribution Expand all Collapse all FUNDACIÓ CLÍNIC PER A LA RECERCA BIOMÈDICA Spain EU contribution No data Address c/villarroel, 170 BARCELONA See on map Total cost No data THE CHANCELLOR, MASTERS AND SCHOLARS OF THE UNIVERSITY OF OXFORD United Kingdom EU contribution No data Address University Offices, Wellington square OXFORD See on map Links Website Opens in new window Total cost No data UNIVERSITA DEGLI STUDI DI TORINO Italy EU contribution No data Address via Guiseppe Verdi 8 TORINO See on map Total cost No data THE UNIVERSITY OF WESTERN AUSTRALIA Australia EU contribution No data Address Roberts Rd SUBIACO See on map Total cost No data THE WALTER AND ELIZA HALL INSTITUTE OF MEDICAL RESEARCH Australia EU contribution No data Address 1G, Royal Parade PARKVILLE, VICTORIA See on map Links Website Opens in new window Total cost No data INTERNATIONAL CENTRE FOR GENETIC ENGINEERING AND BIOTECHNOLOGY India EU contribution No data Address Aruna Asaf Ali marg 10504 NEW DELHI See on map Links Website Opens in new window Total cost No data