Poliomyelitis in children

Poliomyelitis continues to be one of the crippling diseases affecting children in our country. Seventy four percent of the affected children were under the age of two years. Nearly seventy two per cent of these children were totally unprotected and another 18·4% were partially protected. In 66·6% of the children intramuscular infection served as a provocative factor. Spinal poliomyelitis constituted 72%; the rest were bulbospinal 22·5%, bulbar 3·5%, encephalitic type 2·3% and isolated facial palsy 0·5%. The importance of immunization before the age of one year is stressed.     

Poliomyelitis in France: epidemiology and vaccination status.

In France, infants are immunized against paralytic poliomyelitis with enhanced-potency inactivated poliovirus vaccine (eIPV) combined with the diphtheria-tetanus-pertussis vaccine (DTP). Ninety-five percent of all infants in France have received four doses of DTP-eIPV by 24 months of age. No cases of vaccine-associated paralysis, among either recipients or those in contact with recipients, have been reported since 1983, when eIPV became the vaccine of choice. Only three wild indigenous cases have been reported among unvaccinated children in 1988 and 1989, with no cases reported in 1990. Although paralytic poliomyelitis has been virtually eliminated in France, vaccination programs as well as active surveillance of the community and environment for poliovirus circulation should be reinforced to reach the goal of wild poliovirus eradication.     

Poliomyelitis in vaccinated children

Fifty-two children who had received at least 3 properly spaced doses of oral polio-vaccine and had developed acute poliomyelitis inspite of vaccination were studied clinically and serologically. This group (A) was compared with 28 children with poliomyelitis who had not received any vaccination (Group B). A much higher incidence of provocative injection and a better muscle power on presentation was seen in Group A as compared to Group B. Polio-virus type 2 was the commonest etiological agent in Group A (42.3%) whereas type I virus was most commonly seen in Group B (78.6%). A total 53.8% of cases of Group A had protective antibody titres to at least one poliovirus type in the acute phase sera, compared to only 4% from Group B. Six per cent from Group A had protective antibodies to all three virus types, disease in these cases was caused by non-polio agents. Two cases in Group A were possibly vaccine induced paralysis. Recovery, after 60 days, was much better in Group A as compared to Group B. Mortality in the two groups was comparable.     

Poliomyelitis with special reference to immunization status.

One hundred ninety one children below 5 years of age suffering from poliomyelitis were analyzed to find out the immunization status and its correlation with the incidence of poliomyelitis. Effects of age, sex, immunization status and seasonal variation on the morbidity and mortality status were studied. The maximum number of cases were admitted during the months of July (23.6%) and August (23.1%). Of 191 cases, 143 (74.9%) had no immunization and 48 (25.1%) were partially immunized. A total of 155 (81.2%) cases had spinal polio, 23 (12.01%) bulbo-spinal polio, and 13 had (6.8%) bulbar polio. Serious illness (bulbospinal and bulbar type) was more in partially immunized children (25%) as compared to unimmunized children (16.8%). The mortality rate was more than two times higher in the partially immunized (29.6%) as compared to unimmunized children (11.2%). The possible explanation for high mortality in partially immunized children could be due to the adverse effect of OPV which has not been studied so far.