Avian Influenza – The British Veterinary Poultry Association

Why is it important to prevent Avian Influenza?

Avian Influenza (AI) or “bird flu” is a highly contagious and deadly disease that affects a wide range of species including poultry, waterfowl, gamebirds, birds of prey, seabirds and in very rare cases certain mammals, including humans. Avian Influenza can occur as High Pathogenicity (HPAI) and Low Pathogenicity (LPAI) forms. The currently circulating strain is the HPAI form and a very highpercentage of infected birds, including pet poultry, die from the disease. Those that don’t still suffer with ill health from the disease and can spread the virus and so require humane culling and safe disposal. Therefore, minimising the spread of AI nationwide is vital to protect bird health and welfare, and public health.

How is Avian Influenza spread? 

The virus is very infectious – only a small amount of virus causes severe disease in birds and often is fatal! AI is spread through contact with infected birds or the faeces, feathers or bodily fluids from infected birds. Infected wild birds shed large amounts of virus in their faeces and can contaminate the housing, bedding, feed and water of pet and commercial poultry, in so spreading the disease. Rodents, people and physical objects can also carry viruses between birds, for example on their fur, hands or shoes, and transfer infection without knowing it. Birds can become infected with the virus when pecking food, contaminated surfaces and water, or eating bird carcases (e.g. birds of prey and scavenging species). The longer infected birds are alive and the more birds that become infected the more viruses they shed into the environment and the greater the risk of other birds catching AI.

Biosecurity – keeping your birds’ environment clean and free from infectious material is the most effective way to prevent them from catching Avian Influenza.

Staying clean

AI viruses can be destroyed by disinfectants which makes cleansing and disinfection (C&D) very effective at reducing the risk of disease. Prioritise C&D of equipment and surfaces that your birds come in to contact with such as feeders, drinkers and their housing. You can avoid carrying viruses into their environment by using clean poultry house specific footwear that is disinfected before and after each use. Wellington boots are ideal as they can be washed with a hose, scrubbed with a brush to remove muck then disinfected with a foot dip or spray before and after entry into the birds’ enclosure. Foot dips should have a lid, be made of opaque plastic to stop UV light inactivating the product and be replenished when dirty. Take care around small children and pets as disinfectants can be harmful. Please do not enter the bird areas wearing footwear that has been used for other purposes, e.g. walking the dog, since it might be contaminated. Cross contamination of clean items by dirty ones can be prevented being keeping clean and dirty apart. Muck, soil and dirt stop disinfectants working to their full potential therefore it is essential to remove all gross contamination before disinfecting items. Disinfectants also take time to work effectively so please check the contact
time on the product instruction and allow sufficient time before rinsing off disinfectants from equipment and housing. Use DEFRA approved disinfectants that have been proven to destroy AI viruses at the correct dilution. A full list is available at http://disinfectants.defra.gov.uk/DisinfectantsExternal/Default.aspx?Module=ApprovalsList_SI

Preventing contact with infected animals

All types of wild birds can infect your poultry therefore it is necessary to avoid all contact between your birds and wildlife. When a housing order is declared it is essential that all captive birds and poultry are kept under secure cover (housed) for their own protection – this includes pet, hobby and backyard flocks.

Wild birds and rodents are attracted to the food and water available in poultry enclosures:

• Ensure your poultry housing is wild bird and rodent proof by using appropriate materials. Impermeable roofing e.g. boarding, corrugated roofing sheets or tarpaulins over the bird enclosure is most effective at preventing wild bird droppings and feathers from infecting your birds. A solid base (e.g. concrete or paving slabs) or heavy gauge, small diameter wire mesh buried beneath the floor can prevent access by rodents burrowing in. However, if using
  solid flooring provision of deep bedding is important to protect foot health and provide extra enrichment for your birds.
• Cleaning up feed spillages, bird feathers and removing any dead rodents or birds can reduce the risk of your birds being exposed to infectious material , but please use personal protective equipment, e.g. disposable gloves, when handling dead animals, C&D any equipment used then wash your hands thoroughly.
• Fence off ponds and streams and avoid feeding wild birds near to your own birds to avoid contact between domestic and wild birds which might spread AI. Ducks and geese may show little or no disease signs, and are known to be reservoirs and spreaders of AI viruses:
  • Waterfowl must be housed separately from chickens, turkeys and other birds.
  • Avoid direct contact between bird types in adjacent pens as netting and wire fences do not stop the spread of AI.

Safe feed, water and bedding

• Prevent wildlife from contaminating the feed, water and bedding for your birds.
• Feed should be stored in lidded metal containers to protect it from rodents and wild birds.
• Drinkers and feeders should be situated under cover to prevent contamination by wild bird droppings.
• Bedding should be stored in a clean, dry area away from wildlife until needed e.g. in a secure shed or garage.

Record keeping

In the event of an outbreak of Avian Influenza it is essential to track down any possible contacts as quickly as possible to limit onward spread. Good record keeping makes this much easier. Please record all of the following:

• The names, contact details and dates of their visit of all visitors to the bird areas
• The movement of all birds and hatching eggs onto or off your premises including the dates of movements as well as where they came from or are going to.
• When and where any table eggs have moved off the premises if you know the person. If you use an honesty box, record the number of eggs you put in the box and the date you put them there.
• The dates of any deaths in your flock and where their bodies were disposed of. Please note poultry are classified as fallen stock and therefore cannot be buried or double bagged and placed in the bin. They must be disposed of by an approved route. Please contact your local vet who may be able to provide that service.
• When and where used litter, manure or other animal waste has moved off the premises.
• Please note that if your premises is located within a specific disease control zone around a confirmed outbreak movements of live birds, hatching eggs and manure etc are prohibited unless under a licence issued by APHA.

Stay alert

Keeping a close eye on your birds is the best way to recognise any illnesses that might affect their health and welfare. Avian Influenza can cause a range of clinical signs including one or more of the following:

Flock signs – Signs in birds sharing housing
1. Unresponsive, quiet birds, unwell, don’t want to come out and engage as usual. Don’t come for treats as usual.
Sitting around, fluffed up. They may rally temporarily, but will soon tire.
2. Huddling with each other or against coop furniture/equipment like in nests or around drinkers.
3. Unexpected deaths, with other birds also looking unwell.

Bird signs typical with notifiable disease
1. Neurological signs – e.g. shaking, twitching, struggling to balance or just falling asleep & head nodding.
2. Twisted heads or necks leaving birds looking up at the sky or sideways.
3. Swollen, bruised appearance to heads. Facial feathers may stick up in swollen areas.
4. Weak, unable to remain standing for long. Look drunk and may struggle to control their wings.
5. Shivering, actually tremors as birds don’t shiver when they are cold like we do.
6. Bruising or blood spots of the leg, neck or chest. Check in between the feathers.

Bird signs typical with common diseases in hens:
Individual birds with these symptoms, in an otherwise well flock are unlikely to be affected by highly pathogenic
Avian Influenza. However, these signs are very suspicious of Avian Influenza when combined with those previously
mentioned and/or when multiple birds are suddenly affected all at once:
1. Coughing sneezing or gaping, esp. in birds recently wormed for gapeworm
2. Focal facial swelling e.g. around the eyes.
3. Reduction in laying
4. Lethargy
5. Diarrhoea – abnormally coloured or excessively watery faeces

Please contact your vet if you have any concerns about the health of your birds and call the APHA if you suspect they may have Avian Influenza.

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