title: Host-seeking activity of bluetongue virus vectors: endo/exophagy and circadian rhythm of Culicoides in Western Europe.
abstract: Feeding success of free-living hematophagous insects depends on their ability to be active when hosts are available and to reach places where hosts are accessible. When the hematophagous insect is a vector of pathogens, determining the components of host-seeking behavior is of primary interest for the assessment of transmission risk. Our aim was to describe endo/exophagy and circadian host-seeking activity of Palaearctic Culicoides species, which are major biting pests and arbovirus vectors, using drop traps and suction traps baited with four sheep, as bluetongue virus hosts. Collections were carried out in the field, a largely-open stable and an enclosed stable during six collection periods of 24 hours in April/May, in late June and in September/October 2010 in western France. A total of 986 Culicoides belonging to 13 species, mainly C. brunnicans and C. obsoletus, was collected on animal baits. Culicoides brunnicans was clearly exophagic, whereas C. obsoletus was able to enter stables. Culicoides brunnicans exhibited a bimodal pattern of host-seeking activity with peaks just after sunrise and sunset. Culicoides obsoletus was active before sunset in spring and autumn and after sunset in summer, thus illustrating influence of other parameters than light, especially temperature. Description of host-seeking behaviors allowed us to discuss control strategies for transmission of Culicoides-borne pathogens, such as bluetongue virus. However, practical vector-control recommendations are difficult to provide because of the variation in the degree of endophagy and time of host-seeking activity.
authors.affiliation: CIRAD, UMR Contrôle des Maladies, Montpellier, France. elvina.viennet@anu.edu.au
authors.forename: Elvina
authors.initials: E
authors.lastname: Viennet
authors.forename: Claire
authors.initials: C
authors.lastname: Garros
authors.forename: Ignace
authors.initials: I
authors.lastname: Rakotoarivony
authors.forename: Xavier
authors.initials: X
authors.lastname: Allène
authors.forename: Laëtitia
authors.initials: L
authors.lastname: Gardès
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lhoir
authors.forename: Ivanna
authors.initials: I
authors.lastname: Fuentes
authors.forename: Roger
authors.initials: R
authors.lastname: Venail
authors.forename: Didier
authors.initials: D
authors.lastname: Crochet
authors.forename: Renaud
authors.initials: R
authors.lastname: Lancelot
authors.forename: Mickael
authors.initials: M
authors.lastname: Riou
authors.forename: Catherine
authors.initials: C
authors.lastname: Moulia
authors.forename: Thierry
authors.initials: T
authors.lastname: Baldet
authors.forename: Thomas
authors.initials: T
authors.lastname: Balenghien
mesh_terms: D000818:Animals; D001819:Bluetongue / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D001820:Bluetongue virus / Q000254:growth & development* / Q000502:physiology; D002940:Circadian Rhythm / Q000502:physiology; D004175:Diptera / Q000145:classification / Q000502:physiology* / Q000821:virology; D005060:Europe; D005260:Female; D005602:France; D006790:Host-Parasite Interactions; D054884:Host-Pathogen Interactions; D007299:Insect Bites and Stings / Q000503:physiopathology; D007303:Insect Vectors / Q000502:physiology* / Q000821:virology; D008297:Male; D012621:Seasons; D012756:Sheep; D013045:Species Specificity