BFDV is not only the most commonly recognised viral disease of wild psittacine birds, especially in Australia but is a problem globally wherever captive psittacine birds are bred (Raidal, 2004)
Clinical signs of this disease are characterised by feather loss and replacement of this lost plumage by deformed feathers. Baldness can also occur when the feather follicles become inactive. Deformities of the beak and claws can also occur. Birds infected by the virus can live for many years though the condition lasts for several months to a year. The birds usually succumb to secondary infections from secondary bacterial, chlamydial or fungal pathogens. ."
Raidal (2004) reports that, "Secondary disease problems commonly exist in association with BFDV. These include bacterial, fungal and viral infections. Most birds with chronic disease eventually have difficulty eating, lose weight and die. Acutely affected birds often have mucoid or green diarrhoea. These signs are often clinically diagnosed as secondary bacterial or chlamydial infections. However, the virus can cause acute hepatitis, particularly in cockatoos. Some birds may die of acute hepatitis without obvious feather lesions."
Todd (2000) reports that experimentation on BFDV, "Has revealed that its ability to agglutinate erythrocytes was unaffected by incubation at 80°C for 30 min (Raidal & Cross, 1994a), suggesting that this virus is also very stable. It is likely that circoviruses are extremely resistant to environmental degradation, which, in turn, has implications for virus epidemiology and disease control."
Heath et al. (2004) states that, "With the constant movement of birds across geographical borders through trade, there is an increasing risk of spreading the disease into new areas and populations. Coupled to this is the risk of generating unique viruses through recombination between established virus populations and newly introduced viruses."
Gill (2001) states that, "BFDV can devastate breeding programs and cause masked distress to new bird owners and their young birds.”