VPMD: Poliomyelitis (Poliovirus)

What is Polio?

Poliomyelitis is an infectious disease that affects the nervous system and is caused by the poliovirus. The poliovirus is passed from person to person, contaminated water, food or other objects that enter the mouth. The virus then infects and multiplies within the intestines and from there can enter the nervous system, blood stream and feces leading to its symptoms and mode of tranmission.

There are 3 strains of the poliovirus (PV1,PV2 &PV3), current public health agencies report that two out of the three have been eradicated, PV1 remains endemic within Southwest asian countries Pakistan and Afghanistan. Polio has been controlled in most countries as a result of the vaccine since the mid 20th century.

What are the symptoms of poliomyelitis?

Following infection with the poliovirus there are a spectrum of symptoms that one can experience. As with many other infections, some that are infected develop no symptoms at all, while others will develop flulike illness including headache, fever, nausea, muscle pain, vomiting, abdominal pain. These symptoms may progress to include neck pain, limb pain then weakness and eventually paralysis. The type of paralysis that is associated with poliomyletisi is flaccid, when limbs and muscles become limp, depending on what part of the nervous system is affected will determine the areas that are paralyzed. Complications of poliomyelitis range from chronic muscle weakness to permanent paralysis.

How is polio diagnosed?

Polio is diagnosed, most commonly, by demonstrating the virus in the infected persons stool. To increase the chance of detecting the virus, two stool samples within 2 weeks of onset of symptoms are tested.

How is polio treated?

There is no specific treatment for the poliovirus; care is targeted at symptoms and prevention of complications. Due to the infection’s impact on the neuromuscular system, physical therapy is an important component of management.

How to prevent polio?

The Polio vaccine has had significant impact in preventing poliomyelitis in the US. In the US, the 3-dose primary series is given to infants starting at about 2 months old and a booster given between 4 and 6 years old.