Psittacosis Psittacosis Psittacosis—also known as parrot fever, and ornithosis—is a zoonotic infectious disease caused by a bacterium called "Chlamydophila psittaci" and contracted from infected parrots, such as macaws, cockatiels, and budgerigars, and pigeons, sparrows, ducks, hens, gulls and many other species of birds. The incidence of infection in canaries and finches is believed to be lower than in psittacine birds. In certain contexts, the word is used when the disease is carried by any species of birds belonging to the family Psittacidae, whereas "ornithosis" is used when other birds carry the disease. In humans, after an incubation period of 5–19 days,
Krabbe disease may be caused by a lack of active saposin A (a derivative of prosaposin). The buildup of unmetabolized lipids adversely affects the growth of the nerve's protective myelin sheath (the covering that insulates many nerves) resulting in demyelination and severe progressive degeneration of motor skills. As part of a group of disorders known as leukodystrophies, Krabbe disease results from the imperfect growth and development of myelin. GALC deficiency also results in a build-up of a glycosphingolipid called psychosine, which is toxic to oligodendrocytes, a type of non-neuronal cell found in the nervous system, collectively termed neuroglia. The disease may be