According to Animal and Plant Health Agency last report "Emerging threats: pig disease: October to December 2014", the annual trend of increased PRRS diagnoses continued in 2014.
Sixty percent of the diagnoses in 2014 were in the Bury St Edmunds region. It is generally acknowledged that the increasing diversity of PRRS viruses in the GB pig population makes it more likely that the vaccines available will not be able to fully protect against some field virus strains. It is important, when PRRS virus is detected by PCR in vaccinated pigs, follow-up investigations are undertaken to investigate the clinical significance of the detected virus – this is more feasible in pigs with respiratory or systemic disease in which PRRS immunohistochemistry is useful.
Figure 1: GB incidents of PRRS as % of diagnosable submissions
Tuesday March 3, 2015/ Animal and Plant Health Agency/ United Kingdom.
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