Marek’s disease is a highly contagious and widespread viral infection affecting chickens, caused by the Marek’s disease virus (MDV), a herpesvirus. Primarily transmitted through inhalation of dander and feather follicle dust shed by infected birds, it predominantly targets young chickens, causing tumors, immunosuppression, paralysis, and ultimately death. The disease poses significant economic challenges to the poultry industry worldwide. Vaccination plays a pivotal role in controlling Marek’s disease, as it doesn’t eliminate infection but prevents clinical signs and reduces viral shedding. However, the virus can evolve, leading to more virulent strains. Strict biosecurity measures, culling of infected birds, and vaccination strategies are essential components of disease management. Marek’s disease underscores the importance of continuous research and vigilant control measures to mitigate its impact on global poultry populations.