A viral infection of the central nervous system of poultry
Avian encephalomyelitis affects all poultry, typically one- to three-weeks old as well as adults in lay. The disease is spread through contaminated feces and fomites; its incubation period is 1 – 7 days.
Signs of infection include trembling of the head, birds down on their sides, ataxia and dull eyes. Chicks will usually display drowsiness, lack of coordination, unsteady gait, and mortality of 5 – 10%. In adults, cataracts and a drop in egg production may occur.