Question

Explain mode of transmission and symptoms of polio.

Answer 1

Hint: Polio is a highly infectious and life threatening disease that usually affects the children under the five years of age. Polio is also known as poliomyelitis because in some cases the virus can infect the spinal cord causing myelitis (inflammation of spinal cord). Myelitis can result in paralysis, permanent disability or even death.

Complete answer:
• Transmission of Polio
Polio is a disease which is caused by a virus called poliovirus. The virus infects only humans. It is a highly contagious virus that can spread from person to person through direct or indirect contact.

The virus lives in the throat and intestines of infected people and it can be found in droplets, secretions and faeces of infected people. The virus always enters through mouth which can occur in following ways:
- Through contact with faeces (fecal-oral route).
- Droplet transmission during sneezing or coughing.
- Through mouth and nasal secretions like phlegm and mucus.
- Through contaminated food and water.
- Through contaminated items and surfaces.
- The infected person can spread virus for upto 2 weeks even in absence of any symptom.

• Symptoms of Polio
Most of the people infected with poliovirus do not show any symptoms. However, some people may show following symptoms:
- Fever
- Fatigue
- Nausea
- Vomiting
- Headache
- Back or neck pain and stiffness
- Sore throat
- Weakness in muscles
- Loss of reflexes
- Paralysis.

Note: The only way to eradicate polio completely is vaccination as there is no cure for polio. Poliovirus has three strains – Type I, Type II, and Type III. Of these, Type II was already eradicated from the world in 1999. There have been no reported cases of type III since 2012 (last case was in 2012 from Nigeria) and type I only affects two countries of the world which include Pakistan and Afghanistan.