title: Human-Mediated Marine Dispersal Influences the Population Structure of Aedes aegypti in the Philippine Archipelago.
abstract: BACKGROUND
  Dengue virus (DENV) is an extraordinary health burden on global scale, but still lacks effective vaccine. The Philippines is endemic for dengue fever, but massive employment of insecticides favored the development of resistance mutations in its major vector, Aedes aegypti. Alternative vector control strategies consist in releasing artificially modified mosquitos in the wild, but knowledge on their dispersal ability is necessary for a successful implementation. Despite being documented that Ae. aegypti can be passively transported for long distances, no study to date has been aimed at understanding whether human marine transportation can substantially shape the migration patterns of this mosquito. With thousands of islands connected by a dense network of ships, the Philippines is an ideal environment to fill this knowledge gap.
  
  
  RESULTS
  Larvae of Ae. aegypti from 15 seaports in seven major islands of central-western Philippines were collected and genotyped at seven microsatellite loci. Low genetic structure and considerable gene flow was found in the area. Univariate and multivariate regression analyses suggested that anthropic factors (specifically the amount of processed cargo and human population density) can explain the observed population structure, while geographical distance was not correlated. Interestingly, cargo shipments seem to be more efficient than passenger ships in transporting Ae. aegypti. Bayesian clustering confirmed that Ae. aegypti from busy ports are more genetically similar, while populations from idle ports are relatively structured, regardless of the geographical distance that separates them.
  
  
  CONCLUSIONS
  The results confirmed the pivotal role of marine human-mediated long-range dispersal in determining the population structure of Ae. aegypti. Hopefully corroborated by further research, the present findings could assist the design of more effective vector control strategies.
authors.affiliation: Department of Vector Ecology and Environment, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Fonzi
authors.affiliation: Department of Vector Ecology and Environment, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Higa
authors.affiliation: Department of Public Health, University of the Philippines, Manila, Philippines.
authors.forename: Arlene G
authors.initials: AG
authors.lastname: Bertuso
authors.affiliation: Department of Vector Ecology and Environment, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Futami
authors.affiliation: Department of Vector Ecology and Environment, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Minakawa
mesh_terms: D000330:Aedes / Q000235:genetics / Q000502:physiology*; D063147:Animal Distribution / Q000502:physiology*; D000818:Animals; D001499:Bayes Theorem; D016000:Cluster Analysis; D003715:Dengue / Q000517:prevention & control* / Q000635:transmission*; D051456:Gene Flow; D005838:Genotype; D005843:Geography; D006801:Humans; D062312:Islands; D007814:Larva / Q000502:physiology; D018895:Microsatellite Repeats / Q000235:genetics; D010679:Philippines; D011157:Population Dynamics; D012044:Regression Analysis; D012767:Ships