Novel and emerging viruses in pigs
The emergence of pathogenic viruses has the potential to cause huge economic losses in terms of mortality, poor growth rates, and veterinary costs. In order to ensure efficient pig production and to maintain industry competitiveness, it is vital that the emergence of novel pathogenic viruses is closely monitored and any potential disease problems are quickly discovered and controlled.
For example, the emergence of porcine circovirus type II was been estimated to have cost the European Union between €562 million and €900 million per year during peak infection years. It is now known that the virus circulated in pig populations for many years before it became a substantial problem, clearly demonstrating the importance of horizon scanning for possible emerging threats.
While PCV2 associated disease is now largely under control due to vaccination, the importance of continued horizon scanning has recently been emphasised by the recent emergence of a mutant strain in several countries that may be causing clinical disease in vaccinated animals.
A number of small DNA viruses have been identified during the past two decades in pig populations worldwide. As many porcine diseases are multifactorial, co-infections frequently play a crucial role in disease development. As such, it is crucial to monitor the prevalence of these novel parvoviruses and to assess their pathogenicity either alone or in combination with other pathogens.
Additionally, seemingly innocuous viruses could cause economic losses through sub-clinical infection. Enteric infections of pigs can be caused by a wide range of known and emerging viruses e.g. rotavirus, norovirus, coronavirus, sapovirus, pestivirus, astrovirus, enteric adenovirus, torovirus, picobirnavirus.
The role of many of these emerging viruses in enteric disease is poorly understood and conflicting reports have been published regarding their pathogenicity. Monitoring these emerging viruses is key to understanding the complex aetiology of enteric disease.
Research activities into emerging porcine viruses
The porcine virology laboratory is involved in a wide range of research activities aimed at monitoring emerging diseases and investigating potential pathogenicity. These include development of diagnostic tools (real-time PCR, degenerate PCR, rolling circle amplification and virus isolation in cell culture) and the application of these tools in the detection of known, emerging, evolving or novel viruses.
We are investigating potential statistically significant associations with respiratory, enteric and reproductive patholgies, considering viral load aspects of infection and co-infection scenarios.
Next generation sequencing methodologies are being investigated to allow characterisation of the entire viral flora of pigs with particular disease states.
For more information, contact AFBI Stormont