Spatio-Temporal Distribution of Aedes aegypti (Diptera: Culicidae) Mitochondrial Lineages in Cities with Distinct Dengue Incidence Rates Suggests Complex Population Dynamics of the Dengue Vector in Colombia

Abstract

Background Aedes aegypti is the primary vector of the four serotypes of dengue virus (DENV1-4), Chikungunya and yellow fever virus to humans. Previous population genetic studies have revealed a particular genetic structure among the vector populations in the Americas that suggests differences in the ability to transmit DENV. In Colombia, despite its high epidemiologic importance, the genetic population structure and the phylogeographic depiction of Ae. aegypti, as well as its relationship with the epidemiologic landscapes in cities with heterogeneous incidence levels, remains unknown. We conducted a spatiotemporal analysis with the aim of determining the genetic structure and phylogeography of Colombian populations of Ae. aegypti among cities with different eco-epidemiologic characteristics with regard to DENV.Methods/FindingsMitochondrial cytochrome oxidase C subunit 1 (COI) - NADH dehydrogenase subunit 4 (ND4) genes were sequenced and analyzed from 341 adult mosquitoes collected during 2012 and 2013 in the Colombian cities of Bello, Riohacha and Villavicencio, which exhibit low, medium and high levels of incidence of DENV, respectively. The results demonstrated a low genetic differentiation over time and a high genetic structure between the cities due to changes in the frequency of two highly supported genetic groups. The phylogeographic analyses indicated that one group (associated with West African populations) was found in all the cities throughout the sampling while the second group (associated with East African populations) was found in all the samples from Bello and in only one sampling from Riohacha. Environmental factors such as the use of chemical insecticides showed a significant correlation with decreasing genetic diversity, indicating that environmental factors affect the population structure of Ae. aegypti across time and space in these cities.ConclusionsOur results suggest that two Ae. aegypti lineages are present in Colombia; one that is widespread and related to a West African conspecific, and a second that may have been recently introduced and is related to an East African conspecific. The first lineage can be found in cities showing a high incidence of dengue fever and the use of chemical insecticides, whereas the second is present in cities showing a low incidence of dengue fever where the use of chemical insecticides is not constant. This study helps to improve our knowledge of the population structure of Ae. aegypti involved in the diversity of dengue fever epidemiology in Colombia.

Phylogeography and invasion history of Aedes aegypti, the Dengue and Zika mosquito vector in Cape Verde islands (West Africa)

“…samples from Ivory Coast, Nigeria, Cameroon, and Guinea. The levels of nucleotide diversity (π) are similar to values reported in West Africa for both COI and ND4 (Bennett et al, 2016;Paupy et al, 2008), and much lower than the values reported for East Africa (Bennett et al, 2016), America (Eskildsen et al, 2018;Jaimes-Dueñez, Arboleda, Triana-Chávez, & Gómez-Palacio, 2015;Scarpassa, Cardoza, & Cardoso, 2008;Twerdochlib et al, 2012), and Asia (Bosio et al, 2005), possibly due to multiple introduction events in those continents (Bracco, Capurro, Lourenço-de-Oliveira, & Sallum, 2007;Powell & Tabachnick, 2013).…”

Genetic variation in the odorant receptor gene OR4 and bit habits in natural populations of Aedes aegypti from Antioquia department, Colombia

“…aegypti (Atencia et al, 2018;Jaimes et al, 2015) taking into account mitochondrial sequences, it is in this sense that this work contributes to evidence that mosquito populations are also varying in genes that may have epidemiological importance, such as it is the OR4 which in the context of transmission of diseases such as Dengue, Zika or Chicungunya may be involved. It should be noted that due to its short flight range, the active dispersion of this mosquito is limited, especially between sites separated by great distances or between urban environments separated by wild environments, which could expect high genetic differentiation between distant populations.…”

Vector competence and innate immune responses to dengue virus infection in selected laboratory and field‐collected Stegomyia aegypti (= Aedes aegypti)

“…It is likely that field S. aegypti with different levels of VC will emerge as changes in the genetic structure of vector populations influence their ability to transmit dengue (Sim et al ., ). Genetic studies on S. aegypti from Colombia suggest there are two overarching maternal lineages, the overall distribution of which has been influenced by microclimatic variables and reinvasion processes (Jaimes‐Dueñez et al ., ). The process of reinvasion and gene flow across countries can significantly increase population‐level genetic variation (Lima & Scarpassa, ) and hence influence DenV VC.…”