Transboundary Emerging and Exotic Animal Disease/ Exotic Animal Disease Practice Exam

What type of organism primarily causes Marek's disease?

1. Either a virus or a bacterium

2. A bacterium

3. A virus

4. A parasite

The correct answer is: A virus

Marek's disease is primarily caused by a virus, specifically the Marek's disease virus (MDV), which is a member of the Herpesviridae family. This disease affects chickens and is known for inducing lymphomas and other tumors, as well as causing immunosuppression. The virus spreads through the inhalation of dust contaminated with virus-laden dander from infected birds. It has a significant impact on poultry health, leading to high mortality rates and economic losses in the poultry industry. Understanding that the aetiology of Marek's disease is viral is fundamental in implementing vaccination strategies and controlling outbreaks in flocks. Other options mentioned do not pertain to the causative agents of Marek's disease. Specifically, bacteria and parasites play no role in this particular disease. Recognizing the viral nature of Marek's disease is essential in differentiating it from diseases caused by other organisms and is crucial for biosecurity and management practices in poultry farming.