Changes

==Signalment==

==Signalment==

The disease affects '''chickens''' but can also affect quail.  '''Vertical transmission''' is of particular '''importance''' within '''intensive breeding populations'''.  Disease is more '''severe in chicks'''.  Fomites may assist the transmission of the virus.  Immunity occurs once the bird has become infected.

The disease affects '''chickens''' but can also affect quail.  Disease is more '''severe in chicks'''.  Immunity occurs once the bird has become infected.

==Clinical Signs==

==Clinical Signs==

==Epidemiology==

==Epidemiology==

The disease  can be '''spread both horizontally and vertically''', resulting in '''clinical and subclinical infections, respectively'''.   CAV isolates can be distinguished by using restriction endonuclease analysis of amplified DNA, but only a single serotype has so far been detected.  '''Chicks hatching''' from layers of naive flocks over a '''period of 3 to 6 weeks, show clinical signs after 10-14 days of age'''. After this period the breeder layers develop sufficient CAV antibodies to stop the transmission of the virus to the egg.  '''Mortality peaks''' during the '''third week of life''' around 5 to 10% but can be as high as 60%.  '''Horizontal transmission''' can occur in '''older chickens that lack maternal derived antibodies''' from '''faecal-oral route, fomites''' and as the '''virus is excreted''' by a small number of '''vertically infected hatch mates'''.

Fomites may assist the transmission of the virus and the disease  can be '''spread both horizontally and vertically''', resulting in '''clinical and subclinical infections, respectively''' and the latter being of particular '''importance''' to '''intensive breeding populations'''.  

 

CAV isolates can be distinguished by using restriction endonuclease analysis of amplified DNA, but only a single serotype has so far been detected.  '''Chicks hatching''' from layers of naive flocks over a '''period of 3 to 6 weeks, show clinical signs after 10-14 days of age'''. After this period the breeder layers develop sufficient CAV antibodies to stop the transmission of the virus to the egg.  '''Mortality peaks''' during the '''third week of life''' around 5 to 10% but can be as high as 60%.   

 

'''Horizontal transmission''' can occur in '''older chickens that lack maternal derived antibodies''' from '''faecal-oral route, fomites''' and as the '''virus is excreted''' by a small number of '''vertically infected hatch mates'''.

==Distribution==

==Distribution==