Serological survey of bluetongue virus serotype-8 infection in South American camelids in Switzerland (2007-2008)

J Vet Intern Med. 2010 Mar-Apr;24(2):426-30. doi: 10.1111/j.1939-1676.2009.0464.x.

Abstract

Background: Outbreak of bluetongue virus serotype-8 (BTV-8) infection in domestic ruminants in Northern Europe.

Objective: To investigate the South American camelids' (SAC) susceptibility to BTV-8 infection, their role in the epidemiology of the disease, and the use of currently available serological screening tests in SAC in an endemic region.

Animals: Three hundred and fifty-four unvaccinated and 27 vaccinated SAC (170 llamas, 201 alpacas), ranging in age from 1 month to 17 years between June and August 2008. The SAC originated from 44 herds throughout the country, representing 10% of the Swiss SAC population.

Methods: Prospective, observational study of a convenience sample of SAC. Serum samples were analyzed with 2 serological screening tests. When results diverged, a 3rd ELISA was carried out for confirmation (ID Screen Bluetongue Competition ELISA kit).

Results: All sera from the 354 unvaccinated animals were negative in the endemic region. Reliable seroconversion was observed after administration of 2 doses of vaccine.

Conclusions and clinical importance: This study suggests a low susceptibility of SAC to BTV-8 despite the presence of the virus in the cattle and small ruminant population, indicating that SAC do not play a major role in the epidemiology of BTV-8. Furthermore, these results indicate that commercially available serological tests for BTV-8 can be used in SAC.

MeSH terms

  • Animals
  • Bluetongue / epidemiology
  • Bluetongue / virology*
  • Bluetongue virus / classification*
  • Bluetongue virus / isolation & purification*
  • Camelids, New World*
  • Cattle
  • Disease Outbreaks / veterinary
  • Disease Reservoirs / veterinary*
  • Enzyme-Linked Immunosorbent Assay
  • Switzerland / epidemiology