Placental transfer of tetanus toxoid antibodies in Nigerian mothers.

The aim of this study was to assess the efficacy of the tetanus toxoid immunization programme in Nigeria, specifically the placental transfer of antibody to newborn Nigerian babies. Tetanus toxoid antibody levels were measured in 39 mother-baby pairs in Ibadan, Nigeria and compared with 78 British mother-baby pairs. Geometric means of the ratios of cord/mother (sequestration index SI) were 0.776 for Nigerian pairs and 1.306 for British pairs, indicating a limitation in the placental transfer of tetanus toxoid in the Nigerian population. These findings confirm that there is a block in the placental transfer of anti-tetanus toxoid antibodies in African populations which will affect current immunization programmes and requires further investigation.