poliomyelitis

= infantile paralysis; = polio; n.

an infectious virus disease affecting the central nervous system. The virus is excreted in the faeces of an infected person and the disease is therefore most common where sanitation is poor. However, epidemics may occur in more hygienic conditions, where individuals have not acquired immunity to the disease during infancy. Symptoms commence 7–12 days after infection. In most cases paralysis does not occur: in abortive poliomyelitis only the throat and intestines are infected and the symptoms are those of a stomach upset or influenza; in nonparalytic poliomyelitis these symptoms are accompanied by muscle stiffness, particularly in the neck and back. Paralytic poliomyelitis is much less common. The symptoms of the milder forms of the disease are followed by weakness and eventual paralysis of the muscles: in bulbar poliomyelitis the muscles of the respiratory system are involved and breathing is affected. See also post-polio syndrome.

There is no specific treatment, apart from measures to relieve the symptoms: cases of bulbar polio may require the use of a ventilator. Immunization, using the Sabin vaccine (taken orally) or the Salk vaccine (injected), is highly effective.