bluetongue virus

Pictures

Picture	Title	Caption	Copyright
Title Virus particles Caption Five bluetongue virus particles, negatively stained Copyright Geoffrey P. Gard	Virus particles	Five bluetongue virus particles, negatively stained	Geoffrey P. Gard

Identity

Preferred Scientific Name

• bluetongue virus

Taxonomic Tree

• Domain: Virus
•     Unknown: "Positive sense ssRNA viruses"
•         Unknown: "RNA viruses"
•             Family: Reoviridae
•                 Genus: Orbivirus
•                     Species: bluetongue virus

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Pathogen Characteristics

Bluetongue virus is an icosahedral-shaped particle consisting of a segmented double-stranded RNA genome, encapsidated in a double-layered protein coat. Removal of the outer protein layer activates a viral-associated RNA polymerase which transcribes the ten genome segments into 10 mRNAs which are in turn translated into at least seven structural (VP1-VP7) and three non-structural (NS1-NS3) proteins (Huismans and Dijk, 1990). The virions have a diameter of 68-70 nm, comprising an outer capsid around a 54 nm core (Verwoerd and Erasmus, 1994).

The genome segments vary in size from 0.5 kDa to 2.7x10³ kDa, and the viral proteins range in size from 25,000 to 144,000 daltons. VP2 and VP5 form the outer capsid and the other five structural proteins are in the core. VP2 is primarily responsible for the induction of type-specific neutralizing antibodies and its variable sequence results in the 24 recognized serotypes of bluetongue virus (Verwoerd and Erasmus, 1994). The 24 serotypes are designated BLU 1- BLU 24 (Daniels et al., 1996). Variations in other proteins of the virus are responsible for the innumerable strains of the virus and for their varied biological properties. This genetic diversity of bluetongue virus is a consequence of both genetic drift and reassortment of individual gene segments (OIE, 1998).

Disease(s) associated with this pathogen is/are on the list of diseases notifiable to the World Organisation for Animal Health (OIE). The distribution section contains data from OIE's Handistatus database on disease occurrence. Please see the AHPC library for further information from OIE, including the International Animal Health Code and the Manual of Standards for Diagnostic Tests and Vaccines. Also see the website: www.oie.int.

Vectors and Intermediate Hosts

References

Daniels PW; Sendow I; Melville LF, 1996. Epidemiological considerations in the study of bluetongue viruses. Bluetongue disease in Southeast Asia and the Pacific: Proceedings of the First Southeast Asia and Pacific Regional Bluetongue Symposium, Greenlake Hotel, Kunming, P.R. China, 22-24 August 1995., 110-119; 43 ref.

Homan EJ; Gibbs EPJ; Walker JS; Walton TE; Yuill TM; González J; Barreto CH; Greiner EC, 1992. Central American and Caribbean regional bluetongue epidemiologic study: Antecedents and geographic review. Bluetongue, African horse sickness, and related orbiviruses: Proceedings of the Second International Symposium., 99-105; 34 ref.

Huismans H; Dijk AAvan, 1990. Bluetongue virus structural components. Current Topics in Microbiology and Immunology, 162:21-41; 101 ref.

Office International des Epizooties, 1998. Supporting document for the OIE International Animal Health Code chapter 2.1.9 on bluetongue. OIE Ad hoc working group on bluetongue, September 1998.

OIE Handistatus, 2002. World Animal Health Publication and Handistatus II (dataset for 2001). Paris, France: Office International des Epizooties.

OIE Handistatus, 2003. World Animal Health Publication and Handistatus II (dataset for 2002). Paris, France: Office International des Epizooties.

OIE Handistatus, 2004. World Animal Health Publication and Handistatus II (data set for 2003). Paris, France: Office International des Epizooties.

OIE Handistatus, 2005. World Animal Health Publication and Handistatus II (data set for 2004). Paris, France: Office International des Epizooties.

OIE, 2004. Bluetongue in China (People’s Rep. of China). Additional information on the outbreak in August 2004. Disease Information, 17(53).

OIE, 2004. Bluetongue in Croatia. Serological findings in sentinel bovine animals (follow-up report No. 1). Disease Information, 17(49).

OIE, 2004. Bluetongue in France in the island of Corsica. Disease Information, 17(38).

OIE, 2004. Bluetongue in Morocco. Disease Information, 17(39).

OIE, 2004. Bluetongue in Namibia. Disease Information, 17(29).

OIE, 2005. Bluetongue in Portugal. Follow-up report No. 5. Disease Information, 18(2).

Verwoerd DW; Erasmus BJ, 1994. Bluetongue. In: Coetzer JAW, Thomson GR, Tustin RC, eds. Infectious Diseases of Livestock with special reference to Southern Africa. Cape Town, South Africa: Oxford University Press, 443-459.

Distribution Maps