True about polio :
increased muscular activity increases the risk of paralytic polio The incubation period of poliovirus from contact to initial clinical symptoms is usually considered to be 8-12 days with a range of 5-35 days. Poliovirus infection may follow one of the several courses: (i) Inapparent infection It occurs in 80-95% of cases and causes no disease and no sequale (ii) Aboive poliomyelitis It occurs in about 5% of patients. It is a non specific influenza like syndrome which occurs 1-2 week after infection. Fever, malaise, anorexia and headache are prominent features and there may be sore throat and abdominal or muscular pain. The illness is sholived for upto 2-3 days. The physical examination may be normal or may reveal nonspecific pharyngitis, abdominal or muscular 1 tenderness and weakness. Recovery is complete and no neurological signs or sequalae develop. (iii) Nonparalytic poliomyelitis It occurs in 1% of patients infected with poliovirus. They present as soreness and stiffness of the posterior muscles of the neck, trunks and limbs. (iv) Paralytic poliomyelitis Paralytic poliomyelitis develops in about 1% patients causing 3 clinically recognizable syndromes which are (i) Spinal paralytic poliomyelitis (ii) Bulbar poliomyelitis (iii) Polioencephalitis "Pulse polio immunisation is given to all children less than 5 years of age (not 3 years of age)" The risk factors found to precipitate an attack of paralytic polio in individuals infected with polio include: Physical activity immediately following onset of paralysis Skeletal muscle injury due to injection of vaccines or therapeutic agents Pregnancy Malnutrition Immune deficiency Tonsillectomy
Paralytic polio is most common
Spastic paralysis
Increased muscular activity leads to increased paralysis
Polio drop given only in <3 year