Observations on the age and spatial distribution of paralytic poliomyelitis in Ibadan, Nigeria

Poliomyelitis (polio) still remains a great public health problem in developing countries. A study of the distribution of 2205 cases of paralytic poliomyelitis seen in Ibadan City, Nigeria over a 15-year period shows that the incidence of polio is much higher in the central core area of the city where sanitary conditions are poor, whereas in the peripheral parts of the city, where environmental sanitation is better, the incidence of polio is lower. A total of 88.4% of the cases originated from the central core area whereas only 11.6% were from the peripheral area. The polio victims from the peripheral area were, however, disproportionately older than the victims from the core area. It is suggested that in the central core area of Ibadan, where children with the highest risk of polio paralysis reside, immunization against polio should be started much earlier, preferably at birth, while children in the peripheral area who may receive their immunization at a later age (6 months and above) will require booster doses at age 15-18 months and at 5 years of age.