Poliomyelitis (Polio) in Children
What is poliomyelitis?
Poliomyelitis, also called polio, is a highly contagious infectious disease caused
by 3 types of poliovirus. The poliovirus is a virus most recognized for its destruction
to the nervous system causing paralysis. The majority of individuals who are infected
with polio, however, have no symptoms and a few have mild symptoms. According to the
CDC and the World Health Organization (WHO), of those people who do acquire the infection,
1% or fewer may develop paralytic disease. Since the introduction of the polio vaccine
in 1955 and global disease eradication efforts, infections from the poliovirus have
nearly been eliminated.
In countries that are poor, underdeveloped, and do not have access to the vaccine,
polio is still a concern especially for infants and children. The WHO continues its
efforts to eradicate the virus worldwide.
The last case of naturally occurring polio infection in the U.S. was in 1979.
Infants and young children are at greatest risk.
Poliovirus infections are more common during the summer and autumn seasons.
The risk for paralysis from the virus increases with age.
How is poliovirus spread?
Transmission of the poliovirus most often results from fecal-oral contact. Usually,
this happens because of poor hand-washing or from ingestion of contaminated food or
water. Respiratory secretions also spread poliovirus. Those infected with the virus
can excrete the virus in their stool for several weeks. Individuals are most contagious
immediately before the onset of symptoms and soon after they appear.
What are the symptoms of poliomyelitis?
Poliovirus infections can show symptoms in varying degrees of severity. Each child
may experience symptoms differently. The majority of individuals (90% to 95%) have
no symptoms at all. This is referred to as inapparent infection. Three other categories
of polio infection will be discussed:
Abortive poliomyelitis. A mild and short course of the disease with one or more symptoms: fever (up to 103°F
or 39.4°C), decreased appetite, nausea and/or vomiting, sore throat, malaise (not
feeling well), constipation, or abdominal pain.
Nonparalytic poliomyelitis. The symptoms of nonparalytic poliomyelitis include the symptoms for abortive poliomyelitis,
but the headache, nausea, and vomiting may be worse. In addition, symptoms may include
the child feeling sick for a couple of days, and then appear to improve before getting
sick again with pain of the muscles in the neck, trunk, arms, and legs, and stiffness
in the neck and along the spine.
Paralytic poliomyelitis. The symptoms of paralytic poliomyelitis include the symptoms of nonparalytic and abortive
poliomyelitis. In addition, symptoms may include generalized muscle weakness, severe
constipation, muscle wasting, weakened breathing, difficulty swallowing, weak cough,
flushed or blotchy skin, hoarse voice, bladder paralysis, muscle paralysis, irritability
or poor temper control, drooling, or abdominal bloating. The majority of people who
develop paralysis will eventually get some of their strength back, and some will return
to normal. A small percentage will die.
The symptoms of poliomyelitis may resemble other problems or medical conditions. Always
talk with your child's healthcare provider for a diagnosis.
How is poliomyelitis diagnosed?
In addition to a complete medical history and physical exam, diagnostic procedures
for poliomyelitis may include the following:
Cultures of the throat, cerebrospinal fluid, and stool
Test of polio antibodies levels
Lumbar puncture (spinal tap). A special needle is placed into the lower back, into
the spinal canal. This is the area around the spinal cord. The pressure in the spinal
canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF)
can be removed and sent for testing to determine if there is an infection or other
problems. CSF is the fluid that bathes your child's brain and spinal cord.
Discovering a history of the child not receiving the polio vaccine or not completing
the series of polio vaccines
What is the treatment for poliomyelitis?
Your child's healthcare provider will figure out the best treatment for your child
How old your child is
His or her overall health and past health
How sick he or she is
How well your child can handle specific medicines, procedures, or therapies
How long the condition is expected to last
Your opinion or preference
While there is prevention of the poliovirus, there is no treatment to cure children
who become infected. Treatment is supportive. This means that the symptoms may be
treated to improve your child's comfort and recovery. Supportive measures include:
Treatment of pain with analgesics (such as acetaminophen)
Bed rest (until fever is reduced)
Minimal exertion and exercise
Hot packs or heating pads (for muscle pain)
Complications of paralytic poliomyelitis may include permanent paralysis of certain
muscle groups including breathing muscles and leg muscles.
How can poliomyelitis from the virus be prevented?
The following prevention measures will help prevent the spread of the poliovirus:
Proper hygiene and hand washing techniques
Immunization against poliovirus
In the U.S., the polio vaccine is recommended to be given at the following ages:
Between 6 and 18 months
Between ages 4 and 6
Two versions of the vaccine may be given:
IPV. Inactivated polio vaccine (IPV) is given by injection (a shot). This vaccine is given
at all 4 immunization visits. Administration of the IPV cannot cause polio and is
safe to use for individuals with weakened immune systems.
OPV. A weakened version of the virus is given by mouth. This version used to be used in
the U.S., but since it is a live but weakened virus it was shed by the child. Very
rare cases of poliomyelitis developed in close contacts who had a weakened immune
system. Its use in the U.S. and most developed countries has been discontinued.
Infants, children, and adults traveling to countries where polio is still active,
and staying for more than 4 weeks, should get age-appropriate polio vaccines or a
polio booster within 12 months before travel.