About BTV

Bluetongue is an insect borne viral disease.

Classification of BTV

Genus: Orbivirus
Family: Reoviridae.

Serotypes and antigenic drift

BTV is a complex non-enveloped virus with seven structural proteins, three non-structural proteins and a RNA genome consisting of 10 double-stranded segments of different sizes.

Re-assortment of segments can occur during co-infections. In addition, the genome has a high rate of mutations contributing to antigenic drift. At present, 24 serotypes of BTV are recognized. The distribution of the serotypes of BTV tends to be dynamic, with some serotypes being present one year to be replaced the following year by other serotypes. This can cause predominant serotype/s in an area to change with the result that existing vaccine strain/s will no longer be effective in that particular area.

BTV Serotype Distribution

Click on the image below to open a map of the distribution of the different BTV serotypes.