Polio

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What is polio?

Polio is a viral disease which may affect the central nervous system. Since polio immunization has become widespread, cases of polio are very rare.

Who gets polio?

Polio is more common in infants and young children and occurs under conditions of poor hygiene. However, paralysis is more common and more severe when infection occurs in older individuals. In exceedingly rare cases, oral polio vaccine has caused paralytic polio in a person who received the vaccine or in a person who was a close contact of a vaccine recipient.

How is polio spread?

Polio is predominately spread through the feces.

What are the symptoms of polio?

Infection ranges in severity from an inapparent infection to a paralytic disease which may result in death. Symptoms include fever, malaise, headache, nausea and vomiting, excruciating muscle pain and stiffness in the neck and back.

How soon after infection do symptoms appear?

The incubation period is usually six to 20 days for paralytic cases, with a range of three to 35 days.

When and for how long is a person able to spread polio?

Patients are most infectious from seven to 10 days before and after the onset of symptoms. However, patients are potentially contagious as long as the virus is present in the throat and feces. The virus persists in the throat for approximately one week after the onset of illness and is excreted in the feces for several weeks or, occasionally, months.

Does past infection with polio make a person immune?

There are three types of polio virus. Lifelong immunity usually depends on which type of virus a person contracts. Second attacks are rare and result from infection with a polio virus of a different type than the first attack.

What is the treatment for polio?

There is presently no cure for polio. Treatment involves supportive care.

What are the complications associated with polio?

Complications include paralysis (most commonly of the legs). Paralysis of the muscles of respiration and swallowing can be fatal.

Is there a vaccine for polio?

Two types of polio vaccine are available: trivalent oral polio vaccine (tOPV) and inactivated polio vaccine (IPV). In July 1999, the American Academy of Pediatrics and the Advisory Committee on Immunization Practices recommended that IPV be used exclusively in the United States beginning in 2000. The recommended schedule for childhood immunization is for IPV to be given at two, four, and 6-18 months of age and between 4-6 years of age. Adults travelling to countries where polio cases are occurring should review their immunization status.

How can polio be prevented?

Maintaining high levels of polio immunization in the community is the single most effective preventive measure.

Where can I get more information?

UTAH DEPARTMENT OF HEALTH
OFFICE OF EPIDEMIOLOGY
July 2003