Abstract

ABSTRACT
A seroepidemiological study was carried out in Basrah, southern Iraq from November 1997 until the end of
April 1998. Blood samples were collected from 3 sources; Basrah Maternity and Child Hospital, the primary
health care centers in Al-Zubair and Abu-AlKhasib. The relevant information’s were obtained from mothers
through interview and/or vaccination cards. An Enzyme linked Immunosorbent assay (ELISA) was used for
the detection of poliovirus IgG antibodies. Poliovirus antibodies were found in 92.85% with almost full
seroconversion among children above 2 years of age, while seronegative cases were present among infant’s
children below the age of two years and those with old vaccination history and not boosted with additional
booster doses. Malnourished children have relatively lower levels of antibody titer than well nourished children.
Number of vaccine doses given to the child have a significant effect on antibody prevalence where high levels
of immunity were found in children who received 5 doses or more while seronegative cases were detected
among children who had been given 4 doses or less, There were relatively higher seropositivity among
children who received an extra doses during the National Immunization Days (NID) than among those
who did not receive extra dose(s).The antibody levels in the blood is partially affected by age and the number
of vaccine doses given to the child where the proportion of samples with low antibody levels decreased as the
age and number of vaccine doses increases. There was clear evidence for the overtime antibody losses among the
unboosted children.