| | | | | Vertebrate (species and organ) and arthropod | No. isolations/No. tested | No. with antibody/No. tested Test used | Country and region |
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| | Bluetongue is an acute, subacute, and possible chronic virus disease of wild and domestic ruminants (3,10). Sheep often have high morbidity with variable mortality, cattle morbidity is usually low and goat morbidity lower. Although wild ruminants may be severely affected (27), the incrimination of particular species is usually the result of serologic surveys that have shown that a large number of wild ruminants are susceptible (29,33) including epizootics at zoos (9). | | | | | | | | | | Culicoides were first incriminated as vectors in South Africa (6). Virus isolations worldwide have incriminated several species from different Culicoides subgenera but many previous isolations are inconclusively labelled because of taxonomic problems within species complexes. These problems and the likely vector species for each geographic area, primarily belonging to the subgenus Avaritia, are discussed (37); the false assessment of a high vector potential for C. brevitarsis in Australia was prevented through carefully related taxonomic, ecologic, and vector competence studies with field populations of the species of the subgenus Avaritia (38). The primary vector of BLU in the USA is C. variipennis, (Monoculicoides), which is probably a species complex and is the only BLU vector species that has been colonized (17). It has been suggested for South Africa that Culicoides may serve as overwintering BLU hosts in endemic areas with mild winters (24); but pathogenesis studies with C. variipennis reconfirmed the unlikelyhood of transovarian transmission of bluetongue virus (39). | | | | | Amblyomma variegatum | 3 | | Guinea (41) |
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