Introduction:
Poliomyelitis (polio) is a contagious viral illness which is often characterizes by acute onset of flaccid paralysis (polio infection occurs in the digestive tract, then spread to nearby lymph nodes, and in few cases infection is transmitted to the central nervous system). It is also known as an acute communicable disease, entering human body via the mouth and multiplies in the bowel and invades the digestive system. It can cause complete paralysis in a matter of hours, and often affects children under five.
Causes:
Poliomyelitis is caused by enteroviruses classified into types 1, 2 and 3, and all types may cause it.
Who is at risk?
Polio (poliomyelitis) mainly affects children under five.
Polio transmission:
- It is transmitted from a person to another through food and drink contaminated with polio virus.
- Or through dribble and salvia contaminated with polio virus.
Incubation period:
Incubation period is between 3 and 35 days, and 7 and 14 days for paralytic cases.
Symptoms and signs:
Abortive poliomyelitis infection:
It occurs in 4-8% of infections and is characterized by a minor illness with fever for 2 or 3 days, fatigue, muscle pain and probably a headache. These symptoms cannot be differentiated from those caused by many other viruses.
1. Nonparalytic polio:
This usually causes the same mild and flu-like signs and symptoms such as:
- Fever.
- Sore throat.
- Headache.
- Vomiting.
- Fatigue.
- Back pain or stiffness.
- Neck pain or stiffness.
- Pain or stiffness in the arms or legs.
- Muscle weakness.
- Meningitis.
2. Paralytic polio:
It occurs in less than 0.1% of all cases of polio virus infection, and the symptoms are of two phases: The first one is similar to non-paralytic polio, and then come the symptoms of the second phase which include:
- Back pain.
- Flaccid paralysis.
- Stiffness of neck and back.
Diagnosis:
Doctors often recognize polio by symptoms and diagnosis is confirmed by the followings:
Lab test:
A sample of stool, taken from a suspected or contacted case, will be checked (currently accredited examination as recommended by the WHO).
Treatment:
There is no cure for polio; the focus of modern treatment has been on providing relief of symptoms.
Prevention:
At present, there is no cure for polio and the only way to avoid it is through vaccination of children with the approved doses of polio vaccine. In the Kingdom both of the inactivated poliovirus vaccine (IPV) and the oral polio vaccine (OPV) are used. Two oral drops are given to children as per the following schedule:
a- Main doses:
- The first dose of IPV: At the age of two months.
- The second dose of IPV: At the age of four months.
- The third dose of IPV and OPV together: At the age of six months.
b- Activated doses:
- The first dose of OPV: At the age of eighteen months.
- The second dose of OPV: At the age of entering school.
c- Additional doses:
These doses are decided by health authorities based on available data about the spread of the disease and campaigns will be organized to immunize all children.