Poultry production is an extremely efficient, relatively low carbon-footprint way of producing the additional animal protein required for a rapidly expanding human population. Infectious diseases are a continual threat to its sustainability. Vaccination is set to remain the major means of protection against viral diseases of poultry for years to come. We are currently focussed on the viruses that cause avian influenza, infectious bronchitis, and Marek’s disease. These viruses exhibit continual evolution that enables them to work around existing vaccines, and in some cases to cause new forms of disease. Our research, in partnership with vaccine producers, leads to new and more effective vaccines, and provides knowledge to the poultry industry to guide them in their use of vaccines and supplementary disease control measures.
Our scientific priorities are to understand:
- How the attributes of the viruses contribute to their ability to cause disease and to evolve
- How virus and poultry components interact to the benefit of the virus but the detriment of the host
- How the avian immune system and genetic resistance factors contribute to protection against virus infections
These priorities are undertaken with a view to exploiting this knowledge for healthier poultry and sustainable production.
Our research has additional impact arising from:
- Our diagnostic and poultry health expertise
- Development of diagnostic and investigative tools
- Training of poultry industry professionals, diagnosticians and students
- The Institute has several lines of genetically defined chickens, available to all researchers, with differential resistance to various disease agents
The viruses that we study present continual threats to the health of poultry and the poultry industry:
Infectious bronchitis virus (IBV, a coronavirus) is the major infectious cause of economic loss in the chicken industry in the UK. In addition to respiratory and kidney disease, which can kill young chickens, it can affect the reproductive organs, leading to poor egg production. Control by vaccination is made difficult by the existence of a great many serotypes of the virus, with poor cross-protection.
Marek's disease virus (MDV, a herpesvirus), which causes tumours in chickens and turkeys, is largely controlled by vaccines. However, every few years variants of MDV evolve – ironically driven by mass vaccination - which are able to cause disease in vaccinated birds, necessitating the development of yet more vaccines. Moreover, although vaccination prevents disease it does not prevent shedding of the virus, which is then a threat to any chickens or turkeys that have not been vaccinated. The Institute is the Marek's Disease Reference Laboratory on behalf of the World Organisation for Animal Health (OIE).
Outbreaks caused by virulent types of avian influenza virus (AIV, an influenza A virus) are relatively rare in developed countries but are devastating when they do occur. Their threat is the greater because of the high prevalence of AIVs in South East Asia, their spread by movement of poultry and migrating wild birds, and their ability to produce new genetic forms, including ones that can affect humans.