Poliomyelitis

Poliomyelitis
(Polio)
Definition
Poliomyelitis is a very contagious viral infection that can lead to paralysis.
Polio epidemics in the United States were once common throughout the summer months. Because of very effective vaccination programs, polio is now extremely rare in the Western world. However, polio is still a significant problem in parts of Africa and Asia.
Causes
Polio is caused by the poliovirus. You can get the virus from contact with:
• An infected person
• Infected saliva or feces
• Contaminated water or sewage
Poliovirus enters the body through the mouth. It travels to the intestines and reproduces quickly. The virus then travels through the blood and lymph fluid to attack and destroy areas of the nervous system.
Risk Factors
The following factors increase your chances of developing polio:
• Lack of vaccination or incomplete vaccination
• Travel to countries where polio is still common (areas of Africa and Asia)
• Preschool child with immune disorder, exposed to polio virus through vaccination
• Young adult exposed to poliovirus through contact with someone recently vaccinated
• Elderly adult
• Pregnancy
• Strenuous exercise
• Recent tonsillectomy or dental procedure
• Immunodeficiency
Symptoms
If you experience any of these symptoms do not assume it is due to polio. These symptoms may be caused by other, less serious health conditions. Contact your physician if you experience these symptoms.
• Minor illness
o Headache
o Fever
o Sore throat
o Illness lasts about a week
• Major illness
o Fever
o Headache
o Nausea and vomiting
o Diarrhea
o Stiff neck
o Neck pain
o Severe muscle pain
o Muscle spasms
o Muscle weakness
o Paralysis
o Usually asymmetric (affecting each side to varying amounts, or only affecting a single side)
o Muscles become flaccid (loose, floppy)
o Legs more commonly affected than arms
o Muscles required for breathing may be come paralyzed
o Urinary retention
o Decades later, previously stable muscle weakness may worsen due to post-polio syndrome
Diagnosis
Your doctor will ask about your symptoms and medical history, and perform a physical exam.
Tests may include the following:
• Identifying the virus in material from throat swabs, rectal swabs, stool samples, or cerebrospinal fluid
• Immunological tests to prove that the body has responded to the presence of poliovirus by producing antibodies designed to fight the virus
Treatment
Talk with your doctor about the best treatment plan for you. There are no treatments available to rid your body of the poliovirus. Treatment is designed to be supportive, to treat your symptoms, and to help you avoid complications.
Bed Rest
While you still have a fever during the initial phase of illness, you’ll rest in bed. You may be fitted with splints to prevent your joints from becoming too stiff (contractures). You may receive physical therapy during which your limbs will be moved for you (passive exercises).
Fever Control
Analgesic medications such as acetaminophen or nonsteroidal anti-inflammatory agents can be given to lower fever and decrease muscle pain.
Assisted Ventilation
If the muscles you need to breathe become too weak or paralyzed, you may require a period of time on a mechanical ventilator which will take over the work of breathing for you.
Rehabilitation
As soon as possible after your fever passes, you will be given exercises and physical therapy to help you regain mobility and to improve your muscle strength.
Prevention
Two types of vaccines are available to prevent polio. Oral polio vaccine is given by mouth and uses weakened live viruses. Injected vaccine is in shot form and uses killed viruses. Although the risk is very small, there is a tiny chance of actually acquiring polio due to exposure to the live viruses used in the oral polio vaccine. Therefore, the Centers for Disease Control and Prevention now recommend that only injected vaccine be used.
Current immunization recommendations from the Centers for Disease Control and Prevention include:
• Children should receive a series of four immunization injections, at
o Two months
o Four months
o 6-18 months
o 4-6 years
• Adults who have never been immunized should receive a series of three injections if they are at high risk of contracting polio. Risk is increased in adults who
o travel to areas where poliovirus is still common,
o care for individuals with polio, or
o are laboratory workers in labs where poliovirus is handled.