Newcastle disease is a rapidly spreading virus that attacks domestic poultry and other birds. This NebGuide explains disease transmission, symptoms and prevention and control.
Introduction
Newcastle disease virus (NDV) is an acute, rapidly spreading viral disease that affects domestic poultry and other birds. It has a rapid onset and a mortality rate that can be as high as 100 percent. The disease is found worldwide, with the possible exception of some islands and Oceania.
Newcastle disease was first reported in 1926 in the East Indies and then in 1927 at Newcastle-on-Tyne, England, for which it is named. Newcastle disease virus is the type of strain for avian paramyxoviruses. The pathogenicity of NDV strains varies greatly depending on the host. Chickens are highly susceptible, while ducks and geese can be infected and show few or no clinical signs to the same strain.
Strains are designated according to species serotype or the type of birds from which the virus was isolated; the geographical location of isolation (either state or country); and the reference number or name/year of isolation. Numerous strains have been isolated worldwide, resulting in the identification of nine serotypes. Newcastle disease virus is categorized into three groups: lentogenic (mild); mesogenic (intermediate); and velogenic (high).
Velogenic strains are highly likely to cause disease and are easily transmitted. Mesogenic strains are intermediate, and lentogenic strains are least likely to cause disease in chickens. With extremely virulent viruses, the disease may appear suddenly and birds can die before showing any signs of having the virus.
Other factors that help predict the severity of the disease include the host species, age (highly fatal to young chicks), immune stats, and coinfection with other organisms
