B. Clinical Features
"The incubation period is usually 7 - 14 days (range 3 - 35 days). Following ingestion, the virus multiplies in the oropharyngeal and intestinal mucosa. The lymphatic system, in particular the tonsils and the Peyer's patches of the ileum are invaded and the virus enters the blood resulting in a transient viraemia. In a minority of cases, the virus may involve the CNS following dissemination. The following are the possible outcomes following poliovirus infection: -
- Subclinical infection (90 - 95%) - inapparent subclinical infection account for the vast majority of poliovirus infections.
- Abortive infection (4 - 8%) - this group of patients only suffer the minor illness which comprises of influenza-like symptoms such as fever, malaise, drowsiness, headache, nausea, vomiting, constipation and sore throat. Recovery occurs within a few days and the diagnosis can only be made by the laboratory. The minor illness may be accompanied by aseptic meningitis which is similar to the meningitis caused by other enteroviruses and usually resolve without sequelae within 2 - 10 days.
- Major illness (1 - 2%) - the major illness may present 2 - 3 days following the minor illness. In most cases though, the major illness occur without evidence of any preceding minor illness. Signs of aseptic meningitis are common. Involvement of the anterior horn cells lead to flaccid paralysis. Painful muscle spasms and incoordination of non-paralysed muscles may occur. Involvement of the medulla may lead to respiratory paralysis and death. The paralysis usually develops over several days and some recovery may take place. Any effects persisting for more than 6 months are uaually permanent."
So we're talking maybe 1% who had major problems from polio.
Funny, tea cozy--you seem completely unconcerned that more than 1% have vaccine reactions….