Richard Turner MA VetMB MRCVS
St David’s Poultry Team
As I walked around a car park in County Kerry recently, all I could hear was the calling of a large flock of Canada Geese flying low over the wetlands that are in this part of Ireland. As a poultry vet it’s sad that such an evocative sound sends shivers down my spine as I remember the problems of avian influenza (AI) over the last two years, and the serious issues it created for the whole industry.
Looking back
Over the years I have attended many conferences where the fear of AI entering the UK and Ireland has been amplified by the generally accepted idea that this would lead to a massive drop in both egg and meat sales to the public. At the time the most impressive speaker and researcher, Prof Ilaria Capua would come onto the stage, with her first slide of an iceberg and create fear amongst many hardened poultry managers and vets about the impact of AI on the industry. Following that with a picture of Spanish Flu 1918-1920 and it was time to leave the conference and run for the hills!
Maybe it was due to ‘Covid overload’ but for some reason the influenza virus just didn’t hit the public’s list of worries and by all accounts sales of poultry related products didn’t drop by significant amounts during the two winter seasons of AI. Many other factors effected the supply of eggs and meat rather than the presence of AI. As the memory of Covid fades, I do hope that any new cases of AI are not converted into a new 2025 panic.
Managing high pathogenic AI was a massive learning curve for everyone and from a veterinary practice view put huge demands on our team. Our clients suffered a lot more with problems of certification and controls on bird and product movements, but over time systems were developed that allowed for a smoother operation. The financial outcomes were severe, but the disease was controlled. As everyone developed a better understanding of the disease and its epidemiology, the controls adapted as did the requirements for certification. I cannot deny that our clients grew weary and frustrated with the regulatory changes, and I hope now that if AI reappears, we will all be in a better place to reduce the risk of spread and manage bird movements more efficiently.
Producer protection
Insurance for AI is now very difficult and after a quiet late spring and summer it’s so important not to become complacent. Already we are seeing cases of AI close to us on the continent and with the game bird season well underway the issues of wild birds remain a biosecurity challenge. A lot of our clients not only have commercial birds but also enjoy shooting. Last season it was quite a worry to see people travel to attend a shoot alongside a large waterfowl reserve full of migratory ducks and other species. Vehicles were driven onto the shooting grounds and then driven home to another part of the country with little concern for the foot wells of the vehicles. I write this not to stop people shooting or to in anyway comment on the sport itself but to really ask anyone with commercial birds to think hard about what they carry back to their farm from waterfowl areas.
A lot of focus was placed on wild bird spread and whether there is now more resistance in the wild bird population. This has some sense, but after the last winter when cases were a lot lower, it is likely that wild birds hatching this spring will have a lot less maternal immunity. There is a small worry in my mind that whilst controls had an effect, there must have also been a reduction in the challenge, maybe as migratory birds had either died or moved away from the UK. I was wrong as I did think back in the winter of 2022-2023 that as the disease receded like a tidal wave, there would be areas closer to the continent where it remained through the summer. This was not the case thank goodness.
Over the last two years I have noticed around the woodlands where I live that a lot of pigeons seem to succumb easily to fox predation. I wondered at the time how many might have been weakened by disease before being killed and eaten by either a fox or maybe bird of prey. As knowledge developed on the methods of viral spread the role of such predators becomes in my mind more serious.
The wild bird population suffered significantly with absolute horrific stories about the level of mortality in gannet populations as well as many other species. The role of wind spread has been argued and it seems to be the official position remains that this is not a major problem. The virus itself might not last long in the wind, but if attached to fomites such as feathers or dust the situation changes.
After spending a lot of time working in the Middle East where in broiler operations with the highest possible biosecurity in the middle of the desert, mortality could be so high with low pathogenic H9 that millions of birds died in one week, the only eventual control was viral filters on the air inlets. Farms were 1 km apart so whilst air spread might be limited, it can occur at least that far. To be fair these birds also had mycoplasma as well as a range of other respiratory pathogens so it’s not entirely a clear comparison.
Looking ahead
So how does the free range farmer really try to reduce the risk of spread. There is excellent and detailed advice from APHA on the management of biosecurity and I won’t go over it again here other than to say now is the time to review all areas of access to your farm, who is going in and out, who has quietly got their own pet chickens and who might go shooting? Is the feed lorry really clean, how quickly does someone try to drive through the car spray area, and when were the foot dips last changed? On wild birds it becomes more difficult and all you can really do is ensure there is no reason for them to want to share space with your birds. Rodents and farm animals can also transfer AI passively via faecal contamination so please keep your site secure and review with your team the controls and plans that were well rehearsed when AI was prevalent.
The requirements for fly control, netting of air inlets and other structural changes to ensure a better biosecurity building became a major issue for many farms last year and whilst in the early stages of the problem there was some flexibility from regulators, I am sure this will not be the case again. I would certainly suggest to the larger farming groups, packers and integrators that if you haven’t already updated your AI control plan then now is the time without a doubt.
Whilst the sounds of geese flying low in an Autumn evening is a truly evocative thing, the process of bird euthanasia is a significant mental challenge to those involved, so please act now.
Finally, and sadly, if you see dead wild birds, or worse still have unexplained egg drops, mortality or sick birds, please ring your vet.