Dynamics of Plasmodium falciparum genetic diversity among asymptomatic and symptomatic children in three epidemiological areas in Cote d’Ivoire

ABSTRACT

Asymptomatic carriers of Plasmodium are considered a reservoir of the parasite in humans. Therefore, in order to be effective, new malaria elimination strategies must take these targets into account. The aim of this study was to analyse genetic diversity of Plasmodium falciparum among schoolchildren in three epidemiological areas in Côte d’Ivoire. This was a cross-sectional study carried out from May 2015 to April 2016 in a primary school in rural and urban areas of San Pedro, Grand-Bassam and Abengourou, during the rainy season and the dry season. A total of 282 Plasmodium falciparum isolates were genotyped using Nested PCR of Pfmsp1 and Pfmsp2 genes. The overall frequency of K1, Mad20 and RO33 alleles was 81.6%, 53.4% and 57% for Pfmsp1 respectively. For Pfmsp2, this frequency was 84.3% and 72.2% for 3D7 and FC27. K1, Mad20 and FC27 Frequencies were significantly higher in Abengourou compared to other sites. Overall, the frequency of MIs was significantly higher in Abengourou for Pfmsp1 and Pfmsp2. However, Mad20 and RO33 alleles were significantly higher in the rainy season. No significant difference was observed between Pfmsp2 alleles in both seasons. Frequency of the 3D7 allele was significantly higher in symptomatic patients. MIs and COI increased with parasitemia for Pfmsp1and Pfmsp2. The data can be added to that available for monitoring and control of P. falciparum malaria. Further studies combining the entomological inoculation rate and the genetic diversity of P. falciparum will allow us to shed light on our understanding of the epidemiology of this parasite.

KEYWORDS:

• Plasmodium
• asymptomatic carrier
• genetic diversity
• Côte d’Ivoire

Acknowledgments

We would gratefully thank all the staff of the Centre de Recherche et de Lutte contre le Paludisme (CRLP) of the National Institute of Public Health of Côte d’Ivoire (INSP) in particular: DABLE Marius, TANO Konan Dominique, N’CHO Moussan, AKA Bekoin Ferdinand and COULIBALY Abdoul Karim for their technical support. We also thank the inspectors of primary education, teachers and parents and pupils of Grand-Bassam, Abengourou and San Pedro for their participation in this study. We sincerely thank Dr SOULAMA Issiaka for his technical support, AKENJI Blaise, and KOUROUMA Raissa for helping us to correct the English translation of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Financial support

This work was supported through by National Institute of Public Health of Côte d’Ivoire and the DELTAS Africa Initiative [DELGEME grant 107,740/Z/15/Z]. The DELTAS Africa Initiative is an independent funding scheme of the African Academy of Sciences (AAS)’s Alliance for Accelerating Excellence in Science in Africa (AESA) and supported by the New Partnership for Africa’s Development Planning and Coordinating Agency (NEPAD Agency) with funding from the Wellcome Trust [DELGEME grant 107,740/Z/15/Z] and the UK government. The views expressed in this publication are those of the author(s) and not necessarily those of AAS, NEPAD Agency, Wellcome Trust or the UK government.