Maternal and cord blood collected from 33 Nigerian mother–child pairs were tested for measlessepcific IgG. All 33 had protective measles antibodies at the time of delivery with a positive correlation of r = 0.87. Determination of the rate of waning of these antibodies revealed that 58 per cent of these children had lost the protective maternal antibody by the age of 4 months and only 3 per cent of the children had enough antibody to protect them between the ages of 6–9 months. Fifty-five colostrum samples from the same mothers and 347 breastmilk samples collected at various periods of breastfeeding also showed that anti-measles IgA had dropped below the protective cut-off within the first 2 weeks of birth. It is evident that the Nigerian child is born with solid anti-measles antibody but the rate of waning has left a large number unprotected before the first dose of the vaccine. There is an urgent need to review the measles vaccination programme in Nigeria to protect these susceptible infants.