Monday, November 26, 2007

Know Polio for No Polio

Fight against the dreaded disease actually begins with knowing what we are up against

What is polio?

Polio [PO-lee-oh] or poliomyelitis is a viral disease that can damage the nervous system and cause paralysis.

What is the cause of polio?

Polio is caused by any of the three types of polio viruses-- Poliovirus type 1 (PV1 or Mahoney), PV2 (Lansing), and PV3 (Leon). The polio virus lives in the throat and intestinal tract of infected persons. The polio virus enters the body through the mouth, usually from hands contaminated with the stool of an infected person. Sharing contaminated utensils, can also spread the virus.

Is Polio a world-wide phenomenon or restricted to a few countries?

Till a few decades ago, polio was one the world’s most deadly diseases crippling and maiming people all over the world. However due to massive global immunization programs and eradication efforts, polio has been limited to a decreasing number of countries. The greatest risk is now in the Indian subcontinent and, to a lesser extent, in West and Central Africa.

What are the symptoms of polio?

The worst part is that many people infected with the virus have few or no symptoms. The polio virus attacks the nerve cells that control muscle movements causing headache, tiredness, fever, stiff neck and back, and muscle pain. More serious problems happen when the virus invades nerves in the brain and causes paralysis of the muscles used in swallowing and breathing. Invasion of the nerves in the spinal cord can cause paralysis of the arms, legs, or trunk.

How long does it take after the exposure for symptoms to appear?

Usually it takes 7 to 14 days for the symptoms to appear after exposure to the virus. A person with polio can spread the infection as long as the virus is active in their throat or stool. The virus can be found in the throat 1 week after infection and in the stool for 6 weeks or longer.

How is polio diagnosed?

Polio is diagnosed by a blood test or culture.

Who is at risk for polio?

Polio is most common in infants and young children, but complications occur most often in older persons.

What complications can result from polio?

Complications include paralysis, most commonly of the legs. Paralysis of the muscles that control breathing and swallowing can be fatal. In very rare cases, the oral vaccine used to prevent polio can cause polio paralysis in persons who are vaccinated (1 in every 8.1 million doses) and in people who are close contacts of a vaccinated person (1 in every 5 million doses).

What is the treatment for polio?

There is no treatment for polio. A polio patient must receive expert medical care, especially at the beginning of the illness.

How can polio be prevented?

Polio is preventable by immunization. Two types of polio vaccine are available: oral polio vaccine (OPV) and inactivated polio vaccine (IPV). OPV is made with a live but weakened virus. OPV protects vaccinated persons directly. OPV also protects other susceptible persons who are indirectly "vaccinated" as the vaccine virus spreads in the community. Because of wide use of OPV, no cases of paralytic polio caused by naturally circulating polio virus have been reported in the United States since 1979.

IPV is given by injection. The latest thinking worldwide is to give a combination of OPV and IPV for effective protection against polio. The recommended schedule for polio vaccination for children is two doses of IPV at 2 and 4 months of age, followed by two doses of OPV at 12-18 months and 4-6 years. This is expected to reduce the small number of polio cases caused by the oral vaccine.

Booster doses of polio vaccine are also recommended for persons traveling to polio affected areas of the world.

This information is for patient awareness only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health-care provider. For more details consult your family physician or health-care provider