title: Population Genetics of Plasmodium vivax in the Peruvian Amazon.
abstract: BACKGROUND
  Characterizing the parasite dynamics and population structure provides useful information to understand the dynamic of transmission and to better target control interventions. Despite considerable efforts for its control, vivax malaria remains a major health problem in Peru. In this study, we have explored the population genetics of Plasmodium vivax isolates from Iquitos, the main city in the Peruvian Amazon, and 25 neighbouring peri-urban as well as rural villages along the Iquitos-Nauta Road.
  From April to December 2008, 292 P. vivax isolates were collected and successfully genotyped using 14 neutral microsatellites. Analysis of the molecular data revealed a similar proportion of monoclonal and polyclonal infections in urban areas, while in rural areas monoclonal infections were predominant (p = 0.002). Multiplicity of infection was higher in urban (MOI = 1.5-2) compared to rural areas (MOI = 1) (p = 0.003). The level of genetic diversity was similar in all areas (He = 0.66-0.76, p = 0.32) though genetic differentiation between areas was substantial (PHIPT = 0.17, p<0.0001). Principal coordinate analysis showed a marked differentiation between parasites from urban and rural areas. Linkage disequilibrium was detected in all the areas ([Formula: see text] = 0.08-0.49, for all p<0.0001). Gene flow among the areas was stablished through Bayesian analysis of migration models. Recent bottleneck events were detected in 4 areas and a recent parasite expansion in one of the isolated areas. In total, 87 unique haplotypes grouped in 2 or 3 genetic clusters described a sub-structured parasite population.
  
  
  CONCLUSIONS
  Our study shows a sub-structured parasite population with clonal propagation, with most of its components recently affected by bottleneck events. Iquitos city is the main source of parasite spreading for all the peripheral study areas. The routes of transmission and gene flow and the reduction of the parasite population described are important from the public health perspective as well for the formulation of future control policies.
authors.affiliation: Epidemiology for Global Health Institute, University of Antwerp, Antwerp, Belgium.
authors.forename: Christopher
authors.initials: C
authors.lastname: Delgado-Ratto
authors.affiliation: Institute of Tropical Medicine Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.|Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Dionicia
authors.initials: D
authors.lastname: Gamboa
authors.affiliation: Institute of Tropical Medicine Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Veronica E
authors.initials: VE
authors.lastname: Soto-Calle
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Van den Eede
authors.affiliation: Institute of Tropical Medicine Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Eliana
authors.initials: E
authors.lastname: Torres
authors.affiliation: Institute of Tropical Medicine Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Luis
authors.initials: L
authors.lastname: Sánchez-Martínez
authors.affiliation: Institute of Tropical Medicine Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Juan
authors.initials: J
authors.lastname: Contreras-Mancilla
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Anna
authors.initials: A
authors.lastname: Rosanas-Urgell
authors.affiliation: Ministry of Health of Peru, Loreto, Peru.
authors.forename: Hugo
authors.initials: H
authors.lastname: Rodriguez Ferrucci
authors.affiliation: Institute of Tropical Medicine Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Llanos-Cuentas
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Annette
authors.initials: A
authors.lastname: Erhart
authors.affiliation: Epidemiology for Global Health Institute, University of Antwerp, Antwerp, Belgium.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Van Geertruyden
authors.affiliation: Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.|Medical Research Council Unit, Fajara, The Gambia.|London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: Umberto
authors.initials: U
authors.lastname: D'Alessandro
mesh_terms: D008040:Genetic Linkage; D014644:Genetic Variation; D005838:Genotype; D018895:Microsatellite Repeats / Q000235:genetics; D010568:Peru; D010966:Plasmodium vivax / Q000235:genetics*