Department of Quantitative Health Sciences; Department of Pediatrics
Medical Subject Headings
Animals; Antibodies, Protozoan; Antigens, Protozoan; Child; Child, Preschool; Cross-Sectional Studies; Endemic Diseases; Humans; Immunoglobulin G; Incidence; Infant; Kenya; Longitudinal Studies; Malaria, Falciparum; Parasitemia; Plasmodium falciparum; Protozoan Proteins; Sporozoites
Biostatistics | Epidemiology | Health Services Research | Immunology and Infectious Disease | Pediatrics
BACKGROUND: IgG antibodies to pre-erythrocytic antigens are involved in prevention of infection and disease in animal models of malaria but have not been associated with protection against disease in human malaria.
METHODS: Levels of IgG antibodies to circumsporozoite protein (CSP), liver-stage antigen type 1 (LSA-1), and thrombospondin-related adhesive protein (TRAP) were measured in 86 children in a malaria-holoendemic area of Kenya. The children were then monitored for episodes of clinical malaria for 52 weeks.
RESULTS: Children with high levels of IgG antibodies to CSP, LSA-1, and TRAP had a decreased risk of clinical malaria (adjusted hazard ratio, 0.29; 95% confidence interval 0.10-0.81; P = .02), a lower incidence of clinical malaria (P=.006), protection from clinical malaria with a parasite level of > or =4000 parasites/microL (P= .03), and a higher hemoglobin level at enrollment (P= .009), compared with children with lower antibody levels. Protection against malaria morbidity was associated primarily with antibodies to CSP and LSA-1.
CONCLUSIONS: Kenyan children with high levels of IgG antibodies to the pre-erythrocytic antigens CSP, LSA-1, and TRAP have a lower risk of developing clinical malaria than children without high levels of these antibodies. The decreased risk of clinical malaria may be mediated in part by prevention of high-density parasitemia.
Rights and Permissions
© 2008 by the Infectious Diseases Society of America. Citation: J Infect Dis. 2008 Feb 15;197(4):519-26. Link to article on publisher's site
John, Chandy C.; Tande, Aaron J.; Moormann, Ann M.; Sumba, Peter Odada; Lanar, David E.; Min, Xinan M.; and Kazura, James W., "Antibodies to pre-erythrocytic Plasmodium falciparum antigens and risk of clinical malaria in Kenyan children" (2008). Quantitative Health Sciences Publications and Presentations. 402.