title: The effect of virus-blocking Wolbachia on male competitiveness of the dengue vector mosquito, Aedes aegypti.
abstract: BACKGROUND
  The bacterial endosymbiont Wolbachia blocks the transmission of dengue virus by its vector mosquito Aedes aegypti, and is currently being evaluated for control of dengue outbreaks. Wolbachia induces cytoplasmic incompatibility (CI) that results in the developmental failure of offspring in the cross between Wolbachia-infected males and uninfected females. This increases the relative success of infected females in the population, thereby enhancing the spread of the beneficial bacterium. However, Wolbachia spread via CI will only be feasible if infected males are sufficiently competitive in obtaining a mate under field conditions. We tested the effect of Wolbachia on the competitiveness of A. aegypti males under semi-field conditions.
  
  
  RESULTS
  In a series of experiments we exposed uninfected females to Wolbachia-infected and uninfected males simultaneously. We scored the competitiveness of infected males according to the proportion of females producing non-viable eggs due to incompatibility. We found that infected males were equally successful to uninfected males in securing a mate within experimental tents and semi-field cages. This was true for males infected by the benign wMel Wolbachia strain, but also for males infected by the virulent wMelPop (popcorn) strain. By manipulating male size we found that larger males had a higher success than smaller underfed males in the semi-field cages, regardless of their infection status.
  
  
  CONCLUSIONS
  The results indicate that Wolbachia infection does not reduce the competitiveness of A. aegypti males. Moreover, the body size effect suggests a potential advantage for lab-reared Wolbachia-males during a field release episode, due to their better nutrition and larger size. This may promote Wolbachia spread via CI in wild mosquito populations and underscores its potential use for disease control.
authors.affiliation: Mitrani Department of Desert Ecology, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel; School of Public Health and Tropical Medicine and Rehabilitative Sciences, James Cook University, Cairns, Queensland, Australia.
authors.forename: Michal
authors.initials: M
authors.lastname: Segoli
authors.affiliation: Bio21 Institute, Department of Genetics, The University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Ary A
authors.initials: AA
authors.lastname: Hoffmann
authors.affiliation: School of Public Health and Tropical Medicine and Rehabilitative Sciences, James Cook University, Cairns, Queensland, Australia.
authors.forename: Jane
authors.initials: J
authors.lastname: Lloyd
authors.affiliation: School of Public Health and Tropical Medicine and Rehabilitative Sciences, James Cook University, Cairns, Queensland, Australia.
authors.forename: Gavin J
authors.initials: GJ
authors.lastname: Omodei
authors.affiliation: School of Public Health and Tropical Medicine and Rehabilitative Sciences, James Cook University, Cairns, Queensland, Australia.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Ritchie
mesh_terms: D000330:Aedes / Q000382:microbiology* / Q000502:physiology / Q000821:virology; D000818:Animals; D003163:Competitive Behavior / Q000502:physiology*; D003715:Dengue / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission; D003716:Dengue Virus / Q000502:physiology*; D005260:Female; D008297:Male; D012726:Sexual Behavior, Animal / Q000502:physiology; D020577:Wolbachia / Q000502:physiology*