Viruses causing human diseases
Measles, Polio, and Chicken Pox are all diseases caused by viruses. Let's discuss each of these diseases in detail:

Measles:
- Measles is a highly contagious viral infection that spreads through the respiratory system.
- It is characterized by symptoms such as high fever, cough, runny nose, red eyes, and a characteristic rash.
- The measles virus belongs to the genus Morbillivirus in the Paramyxoviridae family.
- Vaccination with the MMR (Measles, Mumps, Rubella) vaccine has been highly effective in preventing measles outbreaks.

Polio:
- Polio, also known as poliomyelitis, is a viral disease that primarily affects the nervous system.
- The poliovirus is transmitted through contaminated food and water, and it can cause paralysis in severe cases.
- There are three strains of poliovirus - type 1, type 2, and type 3. Vaccination with the polio vaccine has led to a significant reduction in polio cases worldwide.

Chicken Pox:
- Chicken Pox is a highly contagious viral infection caused by the varicella-zoster virus.
- It is characterized by a blister-like rash, itching, and flu-like symptoms.
- Chicken Pox is usually a mild disease in children, but it can be more severe in adults or immunocompromised individuals.
- Vaccination with the varicella vaccine has been effective in preventing chickenpox and its complications.
In conclusion, all three diseases - Measles, Polio, and Chicken Pox - are caused by viruses. Vaccination plays a crucial role in preventing these viral infections and reducing their impact on public health.