Although the risk of the SE Asian avian influenza strain (H5N1) arriving in Australia is low, alertness and early detection of avian influenza on a poultry farm would play a huge part in reducing social and economic impacts if an outbreak were to occur in Australia.

Scientific evidence based on genetic analysis of the virus indicates that the previous five avian influenza outbreaks in Australia were not a result of introduction by migratory birds.

After nine years of the H5N1 disease spreading across Asia and recently Europe - during which time approximately 27 million migratory birds visited our shores - Australia remains free of the disease.

However, if it did arrive, early detection would reduce the impact on poultry enterprises and the industry at large, and mitigate the risk to the public and personnel working on the site.

The sooner a disease is detected, the chances of spread are lessened, as are the consequences to the community.

The most sensitive early indicators of avian influenza during the epidemic in the Netherlands in 2003 were a depression in egg production, a higher percentage of floor eggs than normal, and pale eggs.

Other early possible signs include hiding in nest boxes (in the Tamworth AI outbreaks I observed that most of the dead birds were found in the nest boxes), reduction in normal vocalisation, cannibalism, decreased water and feed consumption, apathy and greenish runny droppings.

More obvious signs but not necessarily early signs were: dark blue comb and head, swollen wattles, swollen head, conjunctivitis (eye inflammation), ruffled feathers, coughing, sneezing, gasping, swollen sinuses, head tremors, paralysis, twisted necks, incoordination, lameness and abnormal gait.

Clinical signs can vary depending on a multitude of factors and species.

Mortality could be quick reaching up to 100 per cent in a matter of few days. The window of opportunity for early detection is limited in many cases.

Attention to early signs is very important and while in most cases it may not be avian influenza, nevertheless at a cost of a phone call to a veterinarian, significant spread and impact could be prevented.

NSW DPI also has acquired recently a capacity to detect avian influenza viruses using Polymerase Chain Reaction (PCR). This tool also enables very rapid and reliable results.

Advice to poultry producers and all other birdowners is to think biosecurity, but also understand that biosecurity is only a tool to reduce risks. It does not eliminate the risk.

While the industry at large has improved biosecurity standards on farms, the other important line of national defence is alertness, lateral thinking and early detection.

Assistance is sought from all birdkeepers in Australia to be alert and to report any unusual signs of disease immediately to local vets, agricultural agencies or the animal disease hotline on 1800 675 888.

Contact George Arzey, NSW DPI veterinary officer (poultry), Camden, 4640 6402.

This story appears in Agriculture Today.