Polio is a contagious viral illness that in its most severe form causes nerve injury leading to paralysis, difficulty breathing and sometimes death.
In the U.S., the last case of naturally occurring polio was in 1979. Today, despite a worldwide effort to wipe out polio, poliovirus continues to affect children and adults in parts of Asia and Africa.
The Centers for Disease Control and Prevention (CDC) advises taking precautions to protect yourself from polio if you're traveling anywhere there's a risk of polio.
Adults who have been vaccinated who plan to travel to an area where polio is occurring should receive a booster dose of inactivated poliovirus vaccine (IPV). Immunity after a booster lasts a lifetime.
Symptoms
Although polio can cause paralysis and death, the majority of people who are infected with the virus don't get sick and aren't aware they've been infected.
Nonparalytic polio
Some people who develop symptoms from the poliovirus contract a type of polio that doesn't lead to paralysis (abortive polio). This usually causes the same mild, flu-like signs and symptoms typical of other viral illnesses.
Signs and symptoms, which can last up to 10 days, include:
- Fever
- Sore throat
- Headache
- Vomiting
- Fatigue
- Back pain or stiffness
- Neck pain or stiffness
- Pain or stiffness in the arms or legs
- Muscle weakness or tenderness
Paralytic polio:
This most serious form of the disease is rare. Initial signs and symptoms of paralytic polio, such as fever and headache, often mimic those of nonparalytic polio. Within a week, however, other signs and symptoms appear, including:
- Loss of reflexes
- Severe muscle aches or weakness
- Loose and floppy limbs (flaccid paralysis)
Post-polio syndrome:
Post-polio syndrome is a cluster of disabling signs and symptoms that affect some people years after having polio. Common signs and symptoms include:
- Progressive muscle or joint weakness and pain
- Fatigue
- Muscle wasting (atrophy)
- Breathing or swallowing problems
- Sleep-related breathing disorders, such as sleep apnea
- Decreased tolerance of cold temperatures
Causes
Poliovirus can be transmitted through direct contact with someone infected with the virus or, less commonly, through contaminated food and water. People carrying the poliovirus can spread the virus for weeks in their feces. People who have the virus but don't have symptoms can pass the virus to others.
Risk factors:
Polio mainly affects children younger than 5. However, anyone who hasn't been vaccinated is at risk of developing the disease.
Diagnosis
Doctors often recognize polio by symptoms, such as neck and back stiffness, abnormal reflexes, and difficulty swallowing and breathing. To confirm the diagnosis, a sample of throat secretions, stool or a colorless fluid that surrounds your brain and spinal cord (cerebrospinal fluid) is checked for poliovirus.
Treatment
Because no cure for polio exists, the focus is on increasing comfort, speeding recovery and preventing complications. Supportive treatments include:
- Pain relievers
- Portable ventilators to assist breathing
- Moderate exercise (physical therapy) to prevent deformity and loss of muscle function
