The modification in measles vaccination age as a consequence of the earlier decline of transplacentally transferred antimeasles antibodies in Turkish infants.

The maternal antibodies are gradually decreased at 9 to 12 months in infants. We determined the elimination period of maternal measles antibodies in 34 infants whose mothers had had a history of natural measles previously. Seropositivity rates at sixth and nine months of age were found to be 61.8% and 3.4%, respectively. The very low passive antibody at nine months of age may suggest the measles vaccination could be carried out earlier than just before the critical age of antibody level.