Changes

Endemic in Northern America, Europe and Asia.  

Endemic in Northern America, Europe and Asia.  

Transmission is mainly '''horizontal''' via the faecal-oral route or contaminated environments and equipment/personnel. '''Wild waterfowl''' are often asymptomatic carriers and shedders of DEV.

Transmission is mainly '''horizontal''' via the faecal-oral route or contaminated environments and equipment/personnel.  

 

'''Wild waterfowl''' are often asymptomatic carriers and shedders of DVE.

'''Vertical transmission''' also occurs from persistently infected female ducks to their eggs.

'''Vertical transmission''' also occurs from persistently infected female ducks to their eggs.