Seasonal variation and high multiplicity of first Plasmodium falciparum infections in children from a holoendemic area in Ghana, West Africa.
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.
Kobbe
Robin
R
Infection Epidemiology Group, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. kobbe@bni.uni-hamburg.de
Neuhoff
Rieke
R
Marks
Florian
F
Adjei
Samuel
S
Langefeld
Iris
I
von Reden
Claudia
C
Adjei
Ohene
O
Meyer
Christian G
CG
May
Jürgen
J
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
D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D020066:Merozoite Surface Protein 1; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium