Rabies is a viral disease that affects the central nervous system of humans and other mammals. Once symptoms appear, it is almost always fatal. Symptoms typically begin with flu-like symptoms such as fever, headache, and fatigue, followed by neurological symptoms such as agitation, confusion, and muscle weakness. Later stages of the disease involve hallucinations, seizures, and paralysis. The virus is usually transmitted through the bite of an infected animal, with dogs being the most common vector. While rabies is rare in developed countries due to widespread vaccination of domestic animals, it remains a serious threat in many parts of the world.