‘Bird flu’ is the common name for avian influenza (AI). It is a highly contagious viral disease of birds worldwide. There are many strains of AI virus that cause different infections, ranging from strains that produce little or no symptoms (low pathogenic) to highly pathogenic strains producing severe disease and high death rates in poultry. The much talked about H5N1 strain is highly pathogenic and has caused devastating bird deaths in many parts of the world.
The signs of AI vary and depend on many factors including how pathogenic the virus is, the species and age of infected birds and whether they have other diseases. In very severe forms, such as H5N1, bird flu appears suddenly and birds die quickly. There would be little or no time for any welfare problems. In fact, very acute cases may show no signs at all other than sudden death. It is normal practice in the chicken egg and meat industries that sudden deaths are investigated immediately.
If left unchecked, there would be welfare issues with the less acute forms of AI, as poultry may take up to a week to die. Some affected hens can recover but do not lay eggs again. The importance of skilled workers is paramount. Skilled workers are alert to AI and will note signs and quickly alert a poultry veterinarian to get a diagnosis. Owners of backyard poultry flocks should check their birds every day for any changes. They too need to get advice and have problems investigated straight away. There certainly would be welfare issues for many birds if AI was not noticed and then spread.
In Australia, it is unlikely that poultry with bird flu would suffer for long if an effective emergency plan is in place, with poultry owners following biosecurity procedures. AI is an exotic disease that we certainly do not want to have here. A rapid emergency disease response would spring into action and the property would be quarantined. As AI is so contagious, speed is essential. The national policy is to eradicate AI and limit contact between people and affected birds because there is a risk to human health. Throughout Australia, special teams would be quickly activated and ready to help. This also applies to international specialists, in the same way that Australian teams help with AI outbreaks overseas.
To eradicate AI, skilled operators would humanely destroy all birds in the first affected flock. They would use specific killing, disposal and decontamination procedures wearing full personal protective equipment. Testing would happen in neighbouring properties and in a wider area, together with tracing and testing any birds outside the area that may have been in contact with affected birds.
It is extremely important that, as always, poultry are killed humanely. Those responsible for poultry (including those with backyard poultry) must have a plan in place (rapid emergency disease response) which ensures that all poultry may be killed humanely in the event of a disease outbreak. Methods such as ventilation shutdown are not humane. Poultry veterinarians should be consulted when planning this.
It is possible that welfare issues could arise from quarantine movement restrictions imposed over a large area. Unaffected poultry may not be transported to slaughter as quickly as usual, so bird numbers could build up temporarily. In addition, trucks supplying feed may be delayed. However, contingency plans should quickly solve these problems.
In 2010, a large scale simulation exercise tested how well Australia could deal with an outbreak of AI. It involved exercises aimed at evaluating the ability of industry to respond to and manage a large biosecurity emergency. Simulation exercises show what improvements need to be made to emergency response arrangements.
‘Biosecurity’ simply means protecting the environment, economy, human and animal health from pests and diseases. It includes preventing new ones from arriving in Australia and controlling outbreaks if they do occur. Commercial poultry farmers have well-developed biosecurity systems, however all bird keepers, particularly those with backyard poultry, should practice strict biosecurity.
Birds housed indoors and those which do not come into contact with water fowl are at low risk of becoming infected with AI if simple biosecurity measures are taken — such as preventing them from mixing with wild birds and protecting their environment and food and water supplies from contamination by wild birds. What you need to do to prevent pest and disease outbreaks in your birds is in Avian influenza or bird flu: the key facts on the Department of Agriculture website.
Common signs of AI to look for are:
- sudden death in several birds
- ruffled feathers, unusual head or neck posture, droopy appearance
- birds unable to walk or stand
- birds reluctant to move, eat or drink
- respiratory distress
- swollen head, wattle or comb
- a dramatic drop in egg production.
Immediately report any signs of what could be bird flu, or unusual signs that could be other diseases. The most important contacts are local vets, agriculture departments and the Emergency Animal Disease Watch Hotline on 1800 675 888. All animal owners should have this number handy!
The quicker authorities are alerted to AI, the quicker its spread can be stopped and the quicker it can be eradicated. That way, bird flu should cause no welfare issues to our birds.