General

Polio (also known as poliomyelitis)

What is polio?

Polio (also known as poliomyelitis) is a highly contagious disease caused by a virus that attacks the nervous system. Children younger than 5 years old are more likely to contact the virus than any other group.

According to the World Health Organisation (WHO), one in 200 polio infections will result in permanent paralysis. However, the disease has been largely eradicated thanks to the development of a polio vaccine. The most recent WHO poll, in 2010, reported only 1,352 cases of polio worldwide, (WHO). Thanks to the polio vaccine, the U.S. has not had a reported case of polio since 1979. However, Afghanistan, Pakistan and Nigeria still have frequent outbreaks.

Types of polio

There are three types of polio infections.

Sub-clinical: Approximately 95% of polio cases are sub-clinical and patients may not experience any symptoms. This form of polio does not affect the central nervous system (the brain and the spinal cord).
Non-paralytic: This form which does affects the central nervous system produces only mild symptoms and does not result in paralysis.
Paralytic: This is the rarest and most serious form of polio, which produces full or partial paralysis in a patient. There are three types of paralytic polio: Spinal polio (affect the spine), bubar polio (affects the brainstem), and bulbospinal polio (affects the spine and brainstem).

Mode of transmission

Polio virus is often transmitted from one person through fecal matter. People living in areas with limited access to running water or flush toilet often get the virus from drinking water contaminated by human waste that contain the virus.

In addition, the virus can be spread by contaminated food or water or direct contact with another infected person. According Mayo Clinic, the virus that causes polio is so contagious that anyone living with an infected person will likely become infected themselves (Mayo Clinic).

Pregnant women, people with weaken immune systems, such as HIV+ people and young children are the most susceptible to the polio virus. If you have not been vaccinated, you increase your risk of contracting by;

Travelling to an area that has had a recent polio outbreak.
Taking care of or living with someone infected with polio.
Handling laboratory specimen of the virus.
Having your tonsils removed.
Extreme stress, which can compromise immune system function.

How to prevent polio

The best way to prevent polio is to get vaccinated. Children should get polio shots according to CDC vaccination. Rarely the shots can cause mild or severe allergic reaction including;

Signs and symptoms

Signs and symptoms, which generally last one to 10 days, include: