I remember the first time I saw an iron lung. It was at a museum, tucked away in a corner, its metal frame gleaming under the soft lights. I had read about them in history books, but seeing one in person was different. It was a stark reminder of a time when polio was a looming threat, and the iron lung was a lifeline for many. Polio, or poliomyelitis, is a viral disease that primarily affects children under five. While most infections are mild or asymptomatic, in some cases, the virus can invade the nervous system and cause paralysis. The severity of the disease depends on which part of the nervous system is affected. The Path of the Virus Polio enters the body through the mouth, often from contaminated water or food. It multiplies in the throat and intestines before entering the bloodstream. In rare instances, the virus can invade the central nervous system, leading to inflammation of the spinal cord and brain stem. This can result in paralysis, particularly in the limbs and respir...