Plasmodium vivax and Plasmodium falciparum at the crossroads of exchange among islands in Vanuatu: implications for malaria elimination strategies

PLoS One. 2015 Mar 20;10(3):e0119475. doi: 10.1371/journal.pone.0119475. eCollection 2015.

Abstract

Understanding the transmission and movement of Plasmodium parasites is crucial for malaria elimination and prevention of resurgence. Located at the limit of malaria transmission in the Pacific, Vanuatu is an ideal candidate for elimination programs due to low endemicity and the isolated nature of its island setting. We analyzed the variation in the merozoite surface protein 1 (msp1) and the circumsporozoite protein (csp) of P. falciparum and P. vivax populations to examine the patterns of gene flow and population structures among seven sites on five islands in Vanuatu. Genetic diversity was in general higher in P. vivax than P. falciparum from the same site. In P. vivax, high genetic diversity was likely maintained by greater extent of gene flow among sites and among islands. Consistent with the different patterns of gene flow, the proportion of genetic variance found among islands was substantially higher in P. falciparum (28.81-31.23%) than in P. vivax (-0.53-3.99%). Our data suggest that the current island-by-island malaria elimination strategy in Vanuatu, while adequate for P. falciparum elimination, might need to be complemented with more centrally integrated measures to control P. vivax movement across islands.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gene Flow
  • Genetic Variation
  • Genotype
  • Geography
  • Humans
  • Malaria, Falciparum / epidemiology*
  • Malaria, Falciparum / parasitology*
  • Malaria, Vivax / epidemiology*
  • Malaria, Vivax / parasitology*
  • Molecular Sequence Data
  • Plasmodium falciparum / genetics*
  • Plasmodium vivax / genetics*
  • Protozoan Proteins / genetics
  • Vanuatu / epidemiology

Substances

  • Protozoan Proteins

Associated data

  • GENBANK/AB116596
  • GENBANK/AB116597
  • GENBANK/AB116598
  • GENBANK/AB116599
  • GENBANK/AB116600
  • GENBANK/AB116601
  • GENBANK/AB116602
  • GENBANK/AB116603
  • GENBANK/AB116604
  • GENBANK/AB116605
  • GENBANK/AB116606
  • GENBANK/AB116607
  • GENBANK/AB539022
  • GENBANK/AB539023
  • GENBANK/AB539024
  • GENBANK/AB539025
  • GENBANK/AB539026
  • GENBANK/AB539027
  • GENBANK/AB539028
  • GENBANK/AB539029
  • GENBANK/AB539030
  • GENBANK/AB539031
  • GENBANK/AB539032
  • GENBANK/AB539033
  • GENBANK/AB539034
  • GENBANK/AB539035
  • GENBANK/AB539036
  • GENBANK/AB539037
  • GENBANK/AB539038
  • GENBANK/AB539039
  • GENBANK/AB539040
  • GENBANK/AB539041
  • GENBANK/AB539042
  • GENBANK/AB539043
  • GENBANK/AB539044
  • GENBANK/AB539045
  • GENBANK/AB539540
  • GENBANK/AB539541
  • GENBANK/AB539542
  • GENBANK/AB539543
  • GENBANK/AB539544
  • GENBANK/AB539545
  • GENBANK/AB539546
  • GENBANK/AB539547
  • GENBANK/AB539548
  • GENBANK/AB539549
  • GENBANK/AB539550
  • GENBANK/AB539551
  • GENBANK/AB539552
  • GENBANK/AB539553

Grants and funding

Financial support for this study was provided to AK by the Swedish Research Council (www.vr.se, grant numbers 523-2009-3233, 348-2012-6346, and 348-2013-6311), the Japan Society for the Promotion of Science (JSPS, https://www.jsps.go.jp/english/) Core-to-Core Program, B. Asia-Africa Science Platforms, JSPS KAKENHI (grant numbers 24390141 and 26257504), Health Labour Sciences Research Grant, Research on Global Health issues, and Nagasaki University Institute of Tropical Medicine collaborative research grant. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.