Infantile paralysis, commonly known as polio, refers to an acute and sometimes severe viral illness. Humans are the only natural hosts for the poliovirus. The virus enters through the mouth, multiplying in the throat and intestinal tissues. A small amount of the virus enters the bloodstream, spreading to other areas where it replicates more extensively. A subsequent wave of viremia (presence of the virus in the blood) allows the virus to invade the central nervous system (CNS), particularly targeting the spinal cord and brain, which are the primary areas affected.In cases of CNS involvement, inflammation occurs, especially affecting the anterior horn cells of the spinal cord and the brainstem, which connects the brain's hemispheres to the spinal cord. Polio often presents as a mild illness in 80-90% of clinical cases, mainly in young children, without affecting the CNS. Symptoms include a mild fever, headache, sore throat, and vomiting, appearing 3-5 days after exposure, with recovery in 24-72 hours. This form is known as abortive polio.Polio can also manifest as a more serious illness, which may or may not be paralytic. Symptoms typically arise without preceding illness, particularly in older children and adults, 7-14 days after exposure. These symptoms include fever, severe headache, stiff neck and back, deep muscle pain, and sometimes heightened or altered sensations. There may be no progression beyond this viral presentation, or there may be loss of reflexes and muscle weakness or paralysis.Recovery is usually complete in the abortive and nonparalytic forms. In paralytic cases, about 50% of patients recover without residual paralysis, 25% are left with mild disabilities, and the rest suffer from severe permanent disabilities. The most significant muscle function recovery happens in the first six months, although improvement may continue for up to two years. Physical therapy is crucial during the recovery phase of paralytic polio. The best approach to dealing with polio is through prevention by vaccinating against the virus.President Franklin D. Roosevelt (1882-1945) famously contracted polio and collaborated with the National Foundation/March of Dimes to fundraise for the fight against this once-dreaded disease.
