What is Newcastle Disease (ND)?

Table of Contents☰

About Newcastle Disease (ND):

It is a highly contagious and often severe disease found worldwide that affects birds, including domestic poultry.
It is caused by a virus in the family of paramyxoviruses.
It attacks their respiratory, nervous, and digestive systems.
ND only affects birds, particularly poultry, such as chickens.
It can cause illness and death in large numbers of birds quickly.
Transmission:
- ND is transmitted most often by direct contact with diseased or carrier birds.
- Infected birds may shed the virus in their feces, contaminating the environment.
- Transmission can then occur by direct contact with feces and respiratory discharges or by contaminated food, water, equipment, and human clothing.
- ND viruses can survive for several weeks in the environment, especially in cool weather.
The disease is very contagious. When the virus is introduced into a susceptible flock, virtually all the birds will be infected within two to six days.
Symptoms: Infected birds may show signs of:
- loss of appetite, coughing, gasping, nasal discharge, watery eyes, bright green diarrhoea, and nervous signs such as paralysis and convulsions
- combs and wattles may look swollen, enlarged, and discoloured (purple or blue)
- reduced egg production, and the few eggs that are produced may be soft shelled and malformed.
Treatment:
- There is no treatment for ND, and, in many countries, infected and susceptible birds in the vicinity of an outbreak are culled to contain transmission of the disease.
- Prevention is accomplished through vaccination and strict biosecurity.

Q1: What is a Virus?

A virus is an infectious microbe consisting of a segment of nucleic acid (either DNA or RNA) surrounded by a protein coat. A virus cannot replicate alone; instead, it must infect cells and use components of the host cell to make copies of itself. Often, a virus ends up killing the host cell in the process, causing damage to the host organism. Well-known examples of viruses causing human disease include AIDS, COVID-19, measles and smallpox.

Source: Brazil declares animal health emergency after Newcastle disease case