Objective: To explore serum levels of measles and rubella IgG antibodies among mothers and infants. Methods: According to the inclusion and exclusion criteria, we selected 319 puerperae and their infants in maternal hospitals of Songjiang district November 2016 to February 2017, venous blood were collected and serum measles and rubella IgG antibodies were measured using ELISA. To study the correlation between the level of measles and rubella antibodies in infants and mothers′ by using the Spearman′s correlation analysis. Results: The age at delivery was (29.71±4.25) years old; and the gestational age at delivery was (39.06±1.30) weeks. The positive rate and protection rate of measles antibody in puerperae were 82.5% (243/319) and 43.3% (135/319), the GMC [M (QR)] was 655.74 (251.21-1 299.02) mIU/ml. The positive rate of rubella antibody in puerperae was 61.1% (195/319), the GMC [M (QR)] was 31.34 (11.65-73.61) IU/ml. The positive rate and protection rate of measles antibody in infants were 84.1% (270/321) and 46.1% (148/321), the GMC [M (QR)] was 665.07 (279.63-1 544.07) mIU/ml. The positive rate of rubella antibody in infants was 69.5% (223/321), the GMC [M (QR)] was 40.30 (16.12-98.48) IU/ml. There was statistical difference in measles (Z=-14.64, P<0.001) and rubella (Z=-8.66, P<0.001) antibody levels between mothers and infants. There was positive correlation in measles (r=0.76, P<0.001) and rubella (r=0.86, P<0.001) antibody level between mothers and infants. Conclusion The maternal antibody of measles and rubella had a concentration effect. The level of measles and rubella antibodies in the infants was higher than that in the mothers′ and increased with the increase of the level of measles and rubella antibodies in the mothers.

Measles is an acute respiratory infectious disease caused by the measles virus. It is highly infectious and easy to occur in children. It causes many serious complications such as tracheitis， otitis media and pneumonia. Since the promotion of the measles vaccine in China， the measles epidemic has been effectively controlled. From June 1， 2020， the immunization procedure of measles-containing vaccine for children in Shanghai has been adjusted to one dose of measles， mumps and rubella combined live attenuated vaccine （MMR） at the age of 8 months， 18 months and 6 years. There is generally no local reaction after the injection of the MMR vaccine. A few individuals may have transient fever and scattered rash， which generally fade away by themselves. However， because it is a live vaccine， it may cause vaccine related diseases in extremely rare cases. This paper reports two cases of measles after vaccination with the MMR vaccine.