Antibodies (Abs) are critical for immunity to malaria. However, Plasmodium falciparum specific Abs decline rapidly in absence of reinfection, suggesting impaired immunological memory. This study determines whether residents of Sweden that were treated for malaria following international travel maintained long-lasting malaria-specific Abs and memory B cells (MBCs).
The vast majority of the 1-2 million malaria associated deaths that occur each year are due to anemia and cerebral malaria (the attachment of erythrocytes containing mature forms of Plasmodium falciparum to the endothelial cells that line the vascular beds of the brain). A "model system" for the study of cerebral malaria employs amelanotic melanoma cells as the "target" cells in an in vitro cytoadherence assay.
Artemisinin and its derivatives are endoperoxide-containing antimalarial drugs that appear to form adducts in situ with the Plasmodium falciparum translationally controlled tumor protein (TCTP) homolog. Immunoprecipitation with antibody to recombinant TCTP suggests that adducts may form with both monomeric and dimeric TCTP.
The American Journal of Tropical Medicine and Hygiene
In a treatment re-infection study of 206 Papua New Guinean school children, we examined risk of reinfection and symptomatic malaria caused by different Plasmodium species. Although children acquired a similar number of polymerase chain reaction-detectable Plasmodium falciparum and P. vivax infections in six months of active follow-up (P. falciparum = 5.00, P. vivax = 5.28), they were 21 times more likely to develop symptomatic P. falciparum malaria (1.17/year) than P. vivax malaria (0.06/year). Children greater than nine years of age had a reduced risk of acquiring P.
BACKGROUND: Adequate malaria diagnosis and treatment remain major difficulties in rural sub-Saharan Africa. These issues deserve renewed attention in the light of first-line treatment with expensive artemisinin-combination therapy (ACT) and changing patterns of transmission intensity. This study describes diagnostic and treatment practices in Mto wa Mbu, an area that used to be hyperendemic for malaria, but where no recent assessments of transmission intensity have been conducted. METHODS: Retrospective and prospective data were collected from the two major village health clinics.
Substantial evidence indicates that antibodies to Plasmodium falciparum merozoite antigens play a role in protection from malaria, although the precise targets and mechanisms mediating immunity remain unclear. Different malaria antigens induce distinct immunoglobulin G (IgG) subclass responses, but the importance of different responses in protective immunity from malaria is not known and the factors determining subclass responses in vivo are poorly understood.
BACKGROUND: The efficacy of anti-malarial drugs is determined by the level of parasite susceptibility, anti-malarial drug bioavailability and pharmacokinetics, and host factors including immunity. Host immunity improves the in vivo therapeutic efficacy of anti-malarial drugs, but the mechanism and magnitude of this effect has not been characterized. This study characterized the effects of 'immune' plasma to Plasmodium falciparumon the in vitro susceptibility of P. falciparum to anti-malarial drugs.
BACKGROUND: Intermittent preventive treatment in children (IPTc) is a promising strategy to control malaria morbidity. A significant concern is whether IPTc increases children's susceptibility to subsequent malaria infection by altering their anti-Plasmodium acquired immunity. METHODS: To investigate this concern, IgG antibody (Ab) responses to Plasmodium falciparum schizont extract were measured in Senegalese children (6 months-5 years old) who had received three rounds of IPTc with artesunate + sulphadoxine-pyrimethamine (or placebo) at monthly intervals eight months earlier.
Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America
BACKGROUND: The emergence of Plasmodium falciparum resistance to artemisinins on the Cambodian and Myanmar-Thai borders poses severe threats to malaria control. We investigated whether increasing or splitting the dose of the short-half-life drug artesunate improves parasite clearance in falciparum malaria in the 2 regions.
BACKGROUND: Artemisinin resistance, a long parasite clearance half-life in response to artemisinin, has been described in patients with Plasmodium falciparum malaria in southeast Asia. Few baseline half-lives have been reported from Africa, where artemisinins were recently introduced. METHODS: We treated P. falciparum malaria in 215 Malian children aged 0.5-15 years with artesunate (0, 24, 48 hours) and amodiaquine (72, 96, 120 hours).