Bluetongue virus serotypes 1 and 4 in Sardinia during autumn 2012: new incursions or re-infection with old strains?

Infect Genet Evol. 2013 Oct:19:81-7. doi: 10.1016/j.meegid.2013.06.028. Epub 2013 Jul 6.

Abstract

Since 2000 several bluetongue virus (BTV) incursions have occurred in Sardinia (Italy) involving serotypes 1, 2, 4, 8 and 16. In October 2012, new BT outbreaks caused by BTV-1 and BTV-4 were reported. Nearly 500 flocks were infected and 9238 sheep died because of the infection. When sequenced, Seg-10 of both strains shared 99% similarity at nucleotide level with BTV strains that have circulated in the Mediterranean basin in the last few years. Similarly, Seg-5 sequences of BTV-1 and BTV-4 newly isolated Sardinian strains are identical and cluster together with recent BTV-1 circulating in the Mediterranean Basin and the BTV-4 strains isolated in Tunisia in 2007 and 2009. These BTV-4 strains differ from the ones that circulated in Europe from 2003 to 2005 and appear to be reassortant strains.

Keywords: Bluetongue virus serotype 1; Bluetongue virus serotype 4; Phylogeny; Sardinia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bluetongue / epidemiology
  • Bluetongue / virology*
  • Bluetongue virus / classification*
  • Bluetongue virus / immunology*
  • Bluetongue virus / isolation & purification
  • Italy / epidemiology
  • Phylogeny
  • RNA, Viral / blood
  • Serotyping
  • Sheep
  • Spleen / virology
  • Viral Vaccines / immunology

Substances

  • RNA, Viral
  • Viral Vaccines