The oral susceptibility of South African field populations of Culicoides to African horse sickness virus.
Med Vet Entomol
; 23(4): 367-78, 2009 Dec.
Article
em En
| MEDLINE
| ID: mdl-19941602
ABSTRACT
Twenty-two isolates of African horse sickness virus (AHSV), representing its distinct serotypes, geographical and historical origins, were fed to three populations of South African livestock-associated Culicoides spp. (Diptera, Ceratopogonidae). Infective blood meals included 12 recent isolates, nine historical reference strains and one live attenuated vaccine strain serotype 7 (AHSV-7) of the virus. Field-collected midges were fed through a chicken-skin membrane on sheep blood spiked with one of the viruses, which concentrations ranged from 5.4 to 8.8 log(10)TCID(50)/mL of blood. After 10 days incubation at 23.5 degrees C, AHSV was isolated from 11 Culicoides species. Standard in vitro passaging of AHSV-7, used for the preparation of live attenuated vaccine, did not reduce its ability to infect Culicoides species. Virus recovery rates in orally infected Culicoides midges differed significantly between species and populations, serotypes, isolates and seasons. Significant variations in oral susceptibility recorded in this study emphasize a complex inter-relationship between virus and vector, which is further influenced by multiple intrinsic and extrinsic factors. As it is not possible to standardize all these factors under laboratory conditions, conclusive assessment of the role of field-collected Culicoides midges in the transmission of orbiviruses remains problematic. Nevertheless, results of this study suggest the potential for multi-vector transmission of AHSV virus in South Africa.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ceratopogonidae
/
Doença Equina Africana
/
Vírus da Doença Equina Africana
/
Mordeduras e Picadas de Insetos
Limite:
Animals
País/Região como assunto:
Africa
Idioma:
En
Revista:
Med Vet Entomol
Assunto da revista:
BIOLOGIA
/
MEDICINA VETERINARIA
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
África do Sul