Investigation of bovine ephemeral fever virus transmission by putative dipteran vectors under experimental conditions

Parasites & Vectors

Karin E. Darpel¹  Christopher Sanders¹  Simon Gubbins¹  Jessica E. Stokes¹  Simon Carpenter¹  Anthony R. Fooks²  María del Mar Fernández de Marco²  Luis M. Hernández-Triana²  Nicholas Johnson³ 

[1] The Pirbright Institute, GU24 0NF, Pirbright, Surrey, UK;Virology Department, Animal and Plant Health Agency, Addlestone, KT15 3NB, Surrey, UK;Virology Department, Animal and Plant Health Agency, Addlestone, KT15 3NB, Surrey, UK;Faculty of Health and Medical Science, University of Surrey, Guildford, GU2 7YH, Surrey, UK;

关键词: Vector;    Arbovirus;    Calves;    Culicoides;    Aedes;    Culex;   

DOI  :  10.1186/s13071-020-04485-5

来源: Springer

【 摘 要 】

BackgroundBovine ephemeral fever virus (Rhabdoviridae: Ephemerovirus) (BEFV) causes bovine ephemeral fever (BEF), an economically important disease of cattle and water buffalo. Outbreaks of BEF in Africa, Australia, Asia and the Middle East are characterized by high rates of morbidity and highly efficient transmission between cattle hosts. Despite this, the vectors of BEFV remain poorly defined.MethodsColony lines of biting midges (Culicoides sonorensis) and mosquitoes (Aedes aegypti, Culex pipiens and Culex quinquefasciatus) were infected with a strain of BEFV originating from Israel by feeding on blood–virus suspensions and by intrathoracic inoculation. In addition, in vivo transmission of BEFV was also assessed by allowing C. sonorensis inoculated by the intrathoracic route to feed on male 6 month-old Holstein-Friesian calves.ResultsThere was no evidence of BEFV replication within mosquitoes fed on blood/virus suspensions for mosquitoes of any species tested for each of the three colony lines. In 170 C. sonorensis fed on the blood/virus suspension, BEFV RNA was detected in the bodies of 13 individuals and in the heads of two individuals, indicative of fully disseminated infections and an oral susceptibility rate of 1.2%. BEFV RNA replication was further demonstrated in all C. sonorensis that were inoculated by the intrathoracic route with virus after 5, 6 or 7 days post-infection. Despite this, transmission of BEFV could not be demonstrated when infected C. sonorensis were allowed to feed on calves.ConclusionsNo evidence for infection or dissemination of BEFV (bovine/Israel/2005-6) in mosquitoes of three different species was found. Evidence was found for infection of C. sonorensis by the oral route. However, attempts to transmit BEFV to calves from infected C. sonorensis failed. These results highlight the challenge of defining the natural vector of BEFV and of establishing an in vivo transmission model. The results are discussed with reference to the translation of laboratory-based studies to inference of vector competence in the field.Graphic abstract

【 授权许可】

CC BY