Analysis on measles antibody level in healthy population in Jiangsu, 2018−2020

  Objective  To understand the measles immunization status of healthy population in different age groups in Jiangsu province, monitor the antibody level to measles, analyze the incidence of measles, and provide evidence for the elimination of measles.

  Methods  From 2018 to 2020, the healthy population in seven cities of Jiangsu was selected and divided into six groups, 0−7 month, 8 months−4 years, 5−14 years, 15−24 years, 25−39 years, 40−60 years. Measles IgG was detected by ELISA. The antibody positive rate, high concentration antibody rate and geometric mean concentration (GMC) of measles IgG were calculated.

  Results  A total of 3 132 samples were detected. The overall measles positive rate was 79.25%, the overall GMC was 491.02 mIU/mL and 1 267 samples (40.45%) had high concentration of antibody. The positive rate of IgG and GMC were 90.34% and 741.31 mIU/mL in the population with 1−4 doses of measles containing vaccine immunization. There were statistical significant differences in antibody positive rate and GMC among age groups (χ²=687.192, P<0.001; F=174.734, P<0.001). There were statistical significant difference in measles antibody and GMC among different areas (χ²=72.545, P<0.001; F=19.946, P<0.001).

  Conclusion  The positive rate of measles in healthy population in Jiangsu is high, and the risk for large-scale measles epidemic is low. But the positive rates in some age groups in some areas are low. So the measles immunization should be strengthened. There is no need to adjust existing immune strategies.