Re Cats surviving infection In Dutch experimental studies in which cats were infected with H5N1 virus all but one of the inoculated cats or cats in contact with experimentally infected cats survived. Therefore the Austrian findings (surviving infection) are not all that surprising and do not indicate any "adaptation" to this species. See Kuiken et al Science 2004 Oct 8;306(5694):241  

The cases in Europe again demonstrates that cats are susceptible to H5N1 viruses and some infected cats will die. Cat to cat transmission can occur when cats are kept in close proximity but is unlikely to lead to sustained natural transmission given the low "density" of cats in most households. In places where the disease is controlled in birds we will likely see the end of the disease in cats – as seems to be the case in Thailand. Regards, Les Sims Asia Pacific Veterinary Information Services