Avian Influenza (AI) is one of the most serious biosecurity threats facing UK poultry and game bird farmers. Outbreaks of Highly Pathogenic Avian Influenza (HPAI) have become more frequent and harder to predict and the consequences of inadequate biosecurity can be severe, both for your birds and your business.
The good news is that consistent, well implemented biosecurity measures significantly reduce your risk of an outbreak. This guide covers everything you need to put those measures in place: how HPAI spreads to farms, a practical 10 step biosecurity checklist, the products that should be in every poultry farmer's toolkit, what Avian Influenza Prevention Zones mean for your operation, and how to time your actions to the seasonal risk calendar.
How Does Avian Influenza Spread to Farms?
Highly Pathogenic Avian Influenza (H5N1) is primarily carried by wild migratory birds, particularly waterfowl such as geese, ducks, and gulls which can shed the virus without showing visible symptoms. It spreads to farmed birds through several routes:
Direct contact with wild birds or their droppings give the highest risk factor for free range and game bird operations, particularly during migration season.
Contaminated footwear and clothing, one of the most commonly identified routes of farm to farm spread. One contaminated pair of boots entering a poultry building is enough.
Vehicle and equipment movement such as tyres, wheel arches, and vehicle undersides can carry the virus between premises. Delivery vehicles, feed lorries, and vets are all potential vectors.
Contaminated water sources - watercourses used by wild birds pose a risk for outdoor poultry where birds have access to open water.
People movement like visitors, contractors, and farm staff who have recently been near other poultry flocks must follow strict biosecurity protocols before entering your buildings.
The virus can survive in cool, damp conditions for days or weeks. This is why biosecurity is not just a reactive measure for outbreak periods it must be a consistent, year round discipline, with heightened vigilance during the peak risk window of October to March when migratory birds are most active across the UK.
The Dalton Biosecurity Checklist: 10 Steps Every Poultry Farmer Should Follow
The following checklist covers the core measures that will make the biggest difference to your farm's biosecurity. Work through each step and assess your current position honestly, find the weakest link in your protocol is where the risk is highest.
Control access to your premises. Restrict entry to essential personnel only. Post clear signage at every gate and entrance requiring visitors to report to the farmhouse before approaching poultry housing. Keep a visitor log.
Use dedicated footwear at every building entrance. Keep farm-specific footwear at each poultry building. Staff and visitors must change footwear before entering, never allow footwear worn off farm into bird housing.
Maintain disinfectant foot baths at every entry point. Foot baths must be positioned at every building entrance and kept filled with a virucidal disinfectant effective against enveloped viruses (look for EN14476 certification). Check and refresh the solution daily dirty or over diluted solution provides no protection.
Disinfect all buildings and equipment regularly using a broad spectrum virucidal product. Routine disinfection of housing surfaces, feeding equipment, and drinkers should use a product with proven efficacy against Avian Influenza. Always follow manufacturer dilution rates this is not an area to cut corners.
Wear protective clothing when entering poultry buildings. Provide disposable coveralls for all visitors and contractors entering bird housing. Farm staff should keep dedicated overalls that are laundered at high temperature after each use. Do not wear farm clothing off site.
Disinfect all vehicles before they enter your farm. Require all visitors to disinfect vehicle tyres and wheel arches before driving onto the premises. For high traffic farms, consider a permanent wheel dip or spray arch at the entrance.
Eliminate standing water near poultry housing. Wild birds are attracted to standing water. Remove or fence off any pools, puddles, or watercourses close to bird housing. Inspect the perimeter after heavy rain.
Keep housing clean, dry, and well maintained. Remove and safely dispose of litter regularly. Clean and disinfect drinkers and feeders on a scheduled basis as contaminated water equipment is a key transmission point that is often overlooked.
Operate a clear clean/dirty zone system. Mark a physical boundary between your dirty zone (where vehicles and visitors enter) and your clean zone (bird housing). All personnel must change footwear and PPE when crossing this boundary. Make it visible with painted lines, signage, or physical barriers.
Keep accurate, up to date records. Log all farm visitors, vehicle movements, and cleaning and disinfection activities. This is a biosecurity best practice and is often a legal requirement during disease control events. Good records also help you identify where a potential breach may have occurred.
Recommended Biosecurity Products
Having the right products in stock before risk levels rise means you can respond immediately rather than waiting for delivery during an active outbreak. These are the core categories every poultry and game bird farm should have on hand:
Virucidal Disinfectants
Choose a product with certified efficacy against enveloped viruses (EN14476 standard) and proven activity against Salmonella and Campylobacter. A good virucidal disinfectant is the single most important biosecurity product on any poultry farm. Buy adequate stock before the autumn risk window opens.
Disinfectant Foot Baths
Robust, durable foot baths that are easy to position, fill, and clean at building entrances. Look for baths large enough to fully cover the sole of a boot. Keep a spare in stock so you can clean one while the other remains in use.
Disposable Coveralls and Boot Covers
Single use coveralls for visitors, contractors, and vet visits. Boot covers for short-duration visits where full coveralls aren't necessary. Store a supply near building entrances in a sealed, clean container they're useless if they're contaminated before use.
Vehicle and Equipment Disinfection Sprayers
Knapsack sprayers or hand-pump pressure sprayers for disinfecting vehicle tyres, wheel arches, building surfaces, and large equipment. Essential for farms with regular contractor or delivery vehicle movements.
Farm Cleaning Products
For deep cleaning between flocks and following any suspected disease event. Cleaning must always precede disinfection organic matter (manure, bedding, feathers) inactivates disinfectants. Use a dedicated farm cleaner to remove all organic material before applying your virucidal product.
Avian Influenza Prevention Zones (AIPZs): What They Mean for Your Farm
When HPAI is confirmed in the UK, the Animal and Plant Health Agency (APHA) may declare an Avian Influenza Prevention Zone (AIPZ). These are legal designations not guidance and all poultry keepers within the zone boundary must comply.
What an AIPZ Typically Requires
Enhanced biosecurity measures on all poultry premises within the zone boundary
Regular inspection and disinfection of buildings, equipment, and vehicles
Minimising the movement of birds, people, and equipment between premises
Keeping detailed records of all cleaning, disinfection, and visitor activity
Housing Orders
During higher risk periods or confirmed outbreak zones, DEFRA may issue a mandatory Housing Order requiring all poultry and captive birds to be kept indoors. For free range egg producers and game bird rearers, this is operationally significant.
Prepare in advance. Ensure you have adequate indoor capacity, ventilation, feeding, and drinking equipment to house your full flock at short notice. A Housing Order can be issued with very little warning, and scrambling to source equipment mid outbreak is a poor position to be in. Planning ahead is straightforward; reacting under pressure is not.
Keeping Up to Date
AIPZ declarations and Housing Orders can be issued at short notice during active outbreak periods. Take the following steps now:
Subscribe to DEFRA and APHA alerts at gov.uk/guidance/avian-influenza-bird-flu
Check the APHA interactive AIPZ map regularly from October onwards
Know your local APHA regional office contact in case you need to report suspected disease. If you're unsure whether your premises falls within a zone boundary, contact APHA directly do not wait to find out from a third party
Seasonal Biosecurity Calendar
Avian Influenza can occur at any time of year, but the risk profile is not uniform. Use the calendar below to calibrate your protocols to the season and make sure you're prepared well before the risk window opens each autumn.
Frequently Asked Questions
What disinfectant kills Avian Influenza?
Avian Influenza is an enveloped virus and is susceptible to a wide range of virucidal disinfectants provided they are used correctly. Look for products with EN14476 certification or DEFRA approval. Active ingredients such as glutaraldehyde, peracetic acid, and certain quaternary ammonium compounds are proven effective. Crucially, always follow the manufacturer's dilution instructions and recommended contact times. A correctly diluted product applied for long enough is far more reliable than a stronger solution applied carelessly.
Do I have to house my birds if there's an AIPZ declared in my area?
Not automatically. An AIPZ declaration requires enhanced biosecurity, but mandatory housing only applies if DEFRA issues a specific Housing Order. However, it is strongly advisable to prepare housing capacity in advance so you can comply immediately if an order is issued. Check the APHA interactive map and DEFRA alert service regularly during the risk season.
What PPE do I need during a confirmed local Avian Influenza outbreak?
At minimum: disposable coveralls, boot covers, and gloves for anyone entering bird housing. During a confirmed local outbreak, particularly when carrying out cleaning and disinfection do consider adding FFP2 or higher rated face masks and eye protection. APHA may issue specific guidance depending on the nature of the confirmed case. Consult your vet or APHA regional contact for advice relevant to your specific situation.
Can I still sell birds or eggs during an AIPZ?
Movement of birds and hatching eggs is typically restricted during an AIPZ or confirmed outbreak. Table egg movement may also be subject to conditions. Always check with APHA and your local Trading Standards office before any movement as licences may be required, and non compliance can carry serious penalties. Do not assume historic permissions remain valid during a zone declaration.
How often should I change my foot bath solution?
At minimum, check foot baths daily and change the solution whenever it becomes visibly contaminated with mud, organic matter, or debris. In practice, high-traffic entrances may need refreshing more than once a day. Organic contamination rapidly inactivates disinfectant — a dirty foot bath gives a false sense of security. When in doubt, change it.