Abstract
Background: Diversity in Plasmodium falciparum poses a major threat to malaria control and elimination interventions. This study utilized 12 polymorphic microsatellite (MS) markers and the Msp2 marker to examine diversity, multiplicity of infection (MOI) as well as the population structure of parasites circulating in two sites separated by about 92 km and with varying malaria transmission intensities within the Greater Accra Region of Ghana. Methods: The diversity and MOI of P. falciparum parasites in 160 non-symptomatic volunteers living in Obom (high malaria transmission intensity) and Asutsuare (low malaria transmission intensity) aged between 8 and 60 years was determined using Msp2 genotyping and microsatellite analysis. Results: The prevalence of asymptomatic P. falciparum carriers as well as the parasite density of infections was significantly higher in Obom than in Asutsuare. Samples from Asutsuare and Obom were 100% and 65% clonal, respectively, by Msp2 genotyping but decreased to 50% and 5%, respectively, when determined by MS analysis. The genetic composition of parasites from Obom and Asutsuare were highly distinct, with parasites from Obom being more diverse than those from Asutsuare. Conclusion: Plasmodium falciparum parasites circulating in Obom are genetically more diverse and distinct from those circulating in Asutsuare. The MOI in samples from both Obom and Asutsuare increased when assessed by MS analysis relative to MSP2 genotyping. The TA40 and TA87 loci are useful markers for estimating MOI in high and low parasite prevalence settings.
Highlights
Malaria is still highly endemic throughout Ghana, with the peak transmission season in most parts of the country coinciding with the major raining season
The main tools use to estimate parasite diversity include PCR-based restriction fragment length polymorphism (PCR-RFLP) [28] single nucleotide polymorphism (SNP) [29] molecular typing of the polymorphic regions of merozoite surface protein (Msp)1 and Msp2, the glutamate rich protein (Glurp) genes followed by agarose gel electrophoresis [30]
Obom is a high malaria transmission area with parasite prevalence estimated by microscopy to be 35% [35] and Asutsuare is a low transmission area with microscopy estimated parasite prevalence set at 8.9% [36]
Summary
Malaria is still highly endemic throughout Ghana, with the peak transmission season in most parts of the country coinciding with the major raining season. P. falciparum isolates (including drug resistant parasites) as well as infections harboring multiple. Genetic diversity in the malaria parasite is known to result from the recombination of distinct parasite clones during zygote formation within the mosquito mid gut [11,12]. Genetic diversity and multiplicity of P. falciparum infections are essential parasite indices that could determine the impact of malaria intervention programs as well as the endemicity of parasite infections in varying transmission settings [25,26,27]. The main tools use to estimate parasite diversity include PCR-based restriction fragment length polymorphism (PCR-RFLP) [28] single nucleotide polymorphism (SNP) [29] molecular typing of the polymorphic regions of merozoite surface protein (Msp) and Msp, the glutamate rich protein (Glurp) genes followed by agarose gel electrophoresis [30]. Agarose gel electrophoresis is unable to effectively differentiate between closely sized fragments due to its poor discrimination [34]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
