Newcastle Disease, also known as avian paramyxovirus type 1 (APMV-1), is a highly contagious viral disease that primarily affects birds, particularly domestic poultry and wild birds. The disease is named after the city of Newcastle upon Tyne in England, where it was first identified in 1926. It is caused by a single-stranded RNA virus belonging to the family Paramyxoviridae and the genus Avulavirus.
Newcastle Disease affects a wide range of bird species, including chickens, turkeys, pigeons, ducks, and geese. It has different strains classified as velogenic, mesogenic, or lentogenic, with varying degrees of severity. The velogenic strains, known as viscerotropic velogenic Newcastle Disease (VVND), are highly pathogenic and can cause severe illness, high mortality rates (up to 100% in susceptible birds), and rapid spread within bird populations.
The virus is transmitted through direct contact with infected birds, their droppings, or contaminated objects. It can also be spread through the air or by contaminated feed and water sources. Infected birds typically exhibit respiratory symptoms such as coughing, sneezing, nasal discharge, and labored breathing, as well as nervous system manifestations including tremors, paralysis, and twisted necks. Affected birds also commonly experience a sudden drop in egg production and egg quality.
Newcastle Disease is not known to be a zoonotic disease, meaning it does not pose a significant risk to humans. However, there is a potential threat to the poultry industry, as outbreaks can result in significant economic losses due to trade restrictions and the need for massive culling of affected birds. Vaccination is an effective control measure to prevent and control Newcastle Disease outbreaks in poultry populations.
