Symptoms:

There are three basic patterns of polio infection: subclinical infections, nonparalytic, and paralytic. Approximately 95% of infections are subclinical infections, which may not have symptoms.

SUBCLINICAL INFECTION

• General discomfort or uneasiness (malaise)
• Headache
• Red throat
• Slight fever
• Sore throat
• Vomiting

People with subclinical polio infection might not have symptoms, or their symptoms may last 72 hours or less.

Clinical poliomyelitis affects the central nervous system (brain and spinal cord), and is divided into nonparalytic and paralytic forms. It may occur after recovery from a subclinical infection.

NONPARALYTIC POLIOMYELITIS

• Back pain or backache
• Diarrhea
• Excessive tiredness, fatigue
• Headache
• Irritability
• Leg pain (calf muscles)
• Moderate fever
• Muscle stiffness
• Muscle tenderness and spasm in any area of the body
• Neck pain and stiffness
• Pain in front part of neck
• Pain or stiffness of the back, arms, legs, abdomen
• Skin rash or lesion with pain
• Vomiting

Symptoms usually last 1 - 2 weeks.

PARALYTIC POLIOMYELITIS

• Abnormal sensations (but not loss of sensation) in an area
• Bloated feeling in abdomen
• Breathing difficulty
• Constipation
• Difficulty beginning to urinate
• Drooling
• Fever 5 - 7 days before other symptoms
• Headache
• Irritability or poor temper control
• Muscle contractions or muscle spasms in the calf, neck, or back
• Muscle pain
• Muscle weakness, asymmetrical (only on one side or worse on one side)
  • Location depends on where the spinal cord is affected
  • Progresses to paralysis
  • Rapid onset
• Sensitivity to touch; mild touch may be painful
• Stiff neck and back
• Swallowing difficulty

Signs and tests:

The health care provider may find signs of meningeal irritation (similar to meningitis), such as stiff neck or back stiffness with difficulty bending the neck. The person also might have difficulty lifting the head or lifting the legs when lying flat on the back, and abnormal reflexes.

Tests include:

• Routine CSF examination
• Test for levels of antibodies to the polio virus
• Viral cultures of throat washings, stools, or cerebrospinal fluid (CSF)