HIGHLY CONTAGIOUS DISEASE IN POULTRY – MAREK’S DISEASE


Marek’s disease is a highly contagious viral disease that affects poultry, primarily chickens, and is caused by a herpesvirus known as Marek's disease virus (MDV). It can cause a variety of symptoms, including paralysis, tumors, and in some cases, sudden death. The disease is named after the German veterinarian Josef Marek.
Key Points About Marek's Disease:
Transmission:
The disease spreads through the air and is highly contagious. The virus is shed in the dander and feather dust from infected birds.
It can also be transmitted through contaminated equipment, bedding, or feed.
Symptoms:
Nervous system symptoms: Paralysis of the legs, wings, and neck, which can make birds unable to stand or walk.
Tumors: MDV can cause tumors in various organs, including the liver, kidneys, and spleen, leading to organ failure.
Vision problems: Affected birds may develop "grey eye," which can cause blindness.
Weight loss and overall poor health, leading to death in severe cases.
Incubation Period:
The virus has an incubation period of about 3-4 weeks, although symptoms may not appear until several months after infection.
At-Risk Birds:
Birds of all ages can be infected, but young chicks (typically less than 6 months old) are the most susceptible.
Certain breeds may be more vulnerable than others.
Prevention:
Vaccination: Vaccines against Marek's disease are widely available and are highly effective at preventing the disease. Vaccination is often performed at hatcheries before chicks are distributed.
Biosecurity: Maintaining good biosecurity practices, such as controlling movement of people and equipment, cleaning and disinfecting the environment, and managing exposure to wild birds, can reduce the spread of MDV.
Isolation: Infected birds should be isolated to prevent the spread of the disease to healthy ones.
Treatment:
There is no specific cure for Marek’s disease. Once infected, birds can only be managed to alleviate symptoms, but the disease is often fatal in severe cases.
Infected flocks may need to be culled to prevent further spread.
Economic Impact:
Marek’s disease can have a significant impact on the poultry industry due to losses from mortality, reduced egg production, and the cost of vaccinations and management.
Conclusion:
Marek's disease is a serious concern for poultry producers, but with proper management, including vaccination and biosecurity practices, the spread of the disease can be controlled, and losses minimized. Vaccination remains the most effective way to protect flocks from this contagious disease.