**Question:** All of the following are true regarding acute attack of Polio, except-

A. Polio is a viral infection caused by the enterovirus Paramyxoviridae family, specifically the enterovirus type 1 (EV-A71)
B. Polio is a viral infection that primarily affects the central nervous system
C. Polio primarily affects the respiratory system
D. Polio is a rare disease in the developed world due to widespread vaccination programs

**Correct Answer: C. Polio primarily affects the respiratory system**

**Core Concept:** Polio is a viral infection caused by the enterovirus Paramyxoviridae family, specifically the enterovirus type 1 (EV-A71). Polio primarily affects the central nervous system (CNS), leading to paralysis and other neurological complications.

**Why the Correct Answer is Right:** The correct answer is not mentioned, as all provided options are true regarding the acute attack of Polio. However, option C states that Polio primarily affects the respiratory system, which is incorrect. The virus primarily infects motor neurons in the spinal cord and brainstem, causing damage to the motor neurons, leading to muscle weakness and paralysis.

**Why Each Wrong Option is Incorrect:**

A. Polio is indeed caused by the enterovirus Paramyxoviridae family, specifically the enterovirus type 1 (EV-A71). However, the focus is on the neurological involvement, not respiratory system involvement.
B. Polio primarily affects the central nervous system (CNS), leading to paralysis and other neurological complications. While this option focuses on the CNS involvement, it misleads readers by stating it primarily affects the respiratory system.
D. Polio is a rare disease in the developed world due to widespread vaccination programs. This option discusses the rarity and vaccination efforts, but still does not address the respiratory system involvement.

**Clinical Pearl:** Polio primarily affects the central nervous system, leading to paralysis and other neurological complications, making it essential for medical students and residents to recognize the disease and its clinical presentation, particularly focusing on the neurological manifestations and the role of vaccination in preventing the disease. It is crucial to understand that Polio primarily targets the CNS and is not solely a respiratory disease.