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General Impact 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.”          Location Specific Impacts: Australia   Threat to endangered species: BFDV infects wild and captive psittacine birds in Australia and has been reported in more than 61 psittacine species including threatened psittacines (eg the Swift Parrot, (see Lathamus discolor in IUCN Red List of Threatened Species), and the Norfolk Island Green Parrot (see Cyanoramphus cookii in IUCN Red List of Thrteatened Species) (Orange-bellied Parrot Recovery Team, 1998). A significant cause of death among captive orange-bellied parrots (see Neophema chrysogaster in IUCN Red List of Threatened Species) during the breeding program in 1986 until 1991 was BFD. BFD was first positively diagnosed histologically in orange-bellied parrots by Dr David Pass of MurDOCh University and shown to be caused by a virus BFDV. Since 1990, mortality due to BFD has been practically eliminated in captive bred stock through the relocation of Hobart facility to a warmer, more sheltered site. Assay methods and serum antibody to identify infected birds and to provide more informed care and better hygiene in captive management was undertaken by Department of Animal Health, University of Sydney, and assays for the virus and serum antibody developed (Raidal et al 1993c in Orange-bellied Parrot Recovery Team, 1998). These studies established that wild and captive orange-bellied parrots were exposed to the virus and most captive bred birds survived infection and developed antibodies.