title: Seasonal variation and high multiplicity of first Plasmodium falciparum infections in children from a holoendemic area in Ghana, West Africa.
abstract: OBJECTIVE
  To assess the prevalence and multiplicity of Plasmodium falciparum infections in Ghanaian infants.
  
  
  METHODS
  In an epidemiological study in an area holoendemic for malaria in Ghana, the prevalence and multiplicity of P. falciparum infections (MOI) were assessed in 1069 three month-old infants by typing of the genes encoding the merozoite surface proteins 1 and 2 (msp-1, msp-2) over a recruitment period of one year. Alleles were amplified using allele family-specific polymerase chain reaction (PCR) assays and determined according to their length polymorphisms on a genetic analyzer.
  
  
  RESULTS
  The occurrence of early infections was dependent on the season (month-stratified prevalence 6.4-29.0%). Diversity of msp-alleles was extensive and significantly higher in the dry than in the rainy season.
  
  
  CONCLUSIONS
  The level of infection prevalence and the high multiplicity of infections (median 4, maximum 14 strains per isolate) in the first months of life indicate early contacts with parasites exhibiting a wide repertoire of antigens and, most likely, multiple infections per single mosquito bite.
authors.affiliation: Infection Epidemiology Group, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. kobbe@bni.uni-hamburg.de
authors.forename: Robin
authors.initials: R
authors.lastname: Kobbe
authors.forename: Rieke
authors.initials: R
authors.lastname: Neuhoff
authors.forename: Florian
authors.initials: F
authors.lastname: Marks
authors.forename: Samuel
authors.initials: S
authors.lastname: Adjei
authors.forename: Iris
authors.initials: I
authors.lastname: Langefeld
authors.forename: Claudia
authors.initials: C
authors.lastname: von Reden
authors.forename: Ohene
authors.initials: O
authors.lastname: Adjei
authors.forename: Christian G
authors.initials: CG
authors.lastname: Meyer
authors.forename: Jürgen
authors.initials: J
authors.lastname: May
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics; D044822:Biodiversity; D016054:DNA, Protozoan / Q000235:genetics; D019353:Endemic Diseases; D005838:Genotype; D005869:Ghana / Q000453:epidemiology; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000453:epidemiology* / Q000235:genetics; D020066:Merozoite Surface Protein 1 / Q000235:genetics; D010963:Plasmodium falciparum / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D015800:Protozoan Proteins / Q000235:genetics; D016032:Randomized Controlled Trials as Topic; D012621:Seasons
chemical_list: D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D020066:Merozoite Surface Protein 1; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium