One dose of the mild type vaccine is given after selecting breeder birds. There is no treatment for Newcastle disease. It is caused by a virus that affects chickens only. Other fowl or laboratory animals cannot be infected with this virus. Several distinct strains of the virus exist.
Infectious bronchitis is considered the most contagious of poultry diseases.
When it occurs, all susceptible birds on the premises become infected, regardless of sanitary or quarantine precautions. It can also be spread by mechanical means such as on clothing, poultry crates and equipment. The disease is not egg transmitted and the virus will survive for probably no more than one week in the house when poultry are not present. It is easily destroyed by heat and ordinary disinfectants. The infection is confined to the respiratory system.