Tremovirus
Tremovirus is a virus genus belonging to the Picornaviridae family. The genus has two species, including Avian encephalomyelitis virus. The first avian picornavirus to have its genome sequenced, it causes epidemic tremor in chickens.
Avian encephalomyelitis virus is of economic importance to chicken farmers because it causes a drop in egg production in laying hens, and neurological diseases in chicks less than three weeks old.
The domestic host is the chicken, but it can also infect partridge, turkeys, quail, guineafowl, and pheasants. It has a worldwide distribution.
The virus can be spread by both vertical and horizontal transmission. It is not a zoonosis, meaning that it cannot be transmitted to humans.
Symptoms and diagnosis
Neurological signs such as ataxia, tremor of the head and neck, drooping wings, weakness, paralysis, exercise intolerance and blindness are seen in chicks less than 3 weeks old. In laying hens the disease causes a temporary reduction in egg production.Antibodies can be detected using an ELISA or virus neutralisation. Definitive diagnosis of the disease is by histopathology or virus isolation.