title: Evolutionary potential of the extrinsic incubation period of dengue virus in Aedes aegypti.
abstract: Dengue fever is the most common arboviral disease worldwide. It is caused by dengue viruses (DENV) and the mosquito Aedes aegypti is its primary vector. One of the most powerful determinants of a mosquito's ability to transmit DENV is the length of the extrinsic incubation period (EIP), the time it takes for a virus to be transmitted by a mosquito after consuming an infected blood meal. Here, we repeatedly measured DENV load in the saliva of individual mosquitoes over their lifetime and used this in combination with a breeding design to determine the extent to which EIP might respond to the evolutionary forces of drift and selection. We demonstrated that genetic variation among mosquitoes contributes significantly to transmission potential and length of EIP. We reveal that shorter EIP is genetically correlated with reduced mosquito lifespan, highlighting negative life-history consequences for virus-infected mosquitoes. This work highlights the capacity for local genetic variation in mosquito populations to evolve and to dramatically affect the nature of human outbreaks. It also provides the impetus for isolating mosquito genes that determine EIP. More broadly, our dual experimental approach offers new opportunities for studying the evolutionary potential of transmission traits in other vector/pathogen systems.
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia.
authors.forename: Yixin H
authors.initials: YH
authors.lastname: Ye
authors.affiliation: School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Chenoweth
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Carrasco
authors.affiliation: School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Scott L
authors.initials: SL
authors.lastname: Allen
authors.affiliation: Institute for Health and Biomedical Innovation and School of Biomedical Sciences, Queensland University of Technology, Kelvin Grove, QLD, 4059, Australia.
authors.forename: Francesca D
authors.initials: FD
authors.lastname: Frentiu
authors.affiliation: Public Health Virology, Communicable Diseases Unit, Queensland Health and Forensic and Scientific Services, Coopers Plains, QLD, 4108, Australia.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: van den Hurk
authors.affiliation: School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia.|CSIRO Biosecurity Flagship, Ecosciences Precinct, Dutton Park, QLD, 4102, Australia.
authors.forename: Nigel W
authors.initials: NW
authors.lastname: Beebe
authors.affiliation: School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia. beth.mcgraw@monash.edu.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: McGraw
mesh_terms: D000330:Aedes / Q000235:genetics* / Q000254:growth & development / Q000821:virology; D000818:Animals; D003715:Dengue / Q000635:transmission*; D003716:Dengue Virus / Q000472:pathogenicity*; D019143:Evolution, Molecular; D014644:Genetic Variation; D006801:Humans; D055256:Infectious Disease Incubation Period; D008136:Longevity
keywords: Coevolution; genetic variation; heritability; host/parasite interactions; trade-offs