Early Waning of Maternal Measles and Meningitis C Antibodies

Measles and meningitis C are hot topics in China in recent years. Although China had set the goal of measles elimination, many measles cases were found to be those aged \< 8 months and meningitis C is becoming public health issue since meningitis group A has been controlled at a very low level and little is known on C group. So the investigators designed the observation study on the two antibodies. Maternal antibodies are supposed to wane after birth. Serums of the placenta(0 month), children of 3 months, 5 months and 7 months old will be collected and the geometric mean titers (GMTs) of measles and meningitis C will be confirmed by using the ELISA test.