Mostly CNS affecting viral disease is :

The correct answer is Rabies.

Key Points

• Central Nervous System (CNS) affecting diseases are diseases that affect the central nervous system.
• The most common CNS diseases are:
  • Epilepsy
  • Alzheimer’s
  • Stroke

Rabies:

• Usually transmitted through an animal bite.
• Spread to people from the saliva of infected animals.
• Rhabdoviridae virus caused rabies.
• When there´s a bite from an animal with rabies, the virus attaches to a healthy nerve cell. 
• Then the virus multiplies, making a lot more viruses like itself.

Additional Information

• Leprosy:
  • Also known as Hansen’s disease
  • It is a contagious disease that affects the skin, and nerves.
  • Cause discoloration and lumps on the skin.
  • Caused by the bacteria called Myobacterium laprae.
  • Leprosy can be transmitted during close contact with the affected person.
• Smallpox:
  • It is an infectious disease caused by the Variola virus.
  • WHO declared its eradication in 1978.
  • The last case of smallpox was found in 1977.
• Covid 19:
  • It is an infectious disease caused by the most recently discovered coronavirus.
  • The first known case was identified in Wuhan, China, in December 2019.