Prevalence of Protective Measles Virus Antibody Levels in Umbilical Cord Blood Samples and Sera of Mothers and Transplacental Transport Ratio in Turkey.

In Turkey, the Measles Elimination Program has been implemented since 2002. The aim of this study was to evaluate the measles-specific antibody levels of mothers admitted to a hospital for birth and their infants, to determine the factors influencing the antibody levels of both, and to evaluate the transplacental transport ratio. We selected healthy women who came to the hospital for birth and their healthy newborns. We collected blood samples from 1,547 mothers and 1,529 infants. The protective prevalence of measles antibody levels of mothers was 80% (95% confidence interval [CI]: 78-82%) and that of newborns was 85% (95% CI: 83-86%). The antibody levels of mothers and newborns were positively linearly correlated (R: 0.922, p < 0.001) and were associated with parity (p < 0.001). The ratio of neonatal to maternal antibody levels increased with gestational age. The protective levels were 1.6 times higher (95% CI: 1.1-2.4) in mothers ≥ 32 years of age and 2.1 times higher (95% CI: 1.4-3.3) in naturally immune mothers. Two factors affecting the antibody levels of newborns were the mothers' antibody levels and their immunization status. The antibody level of mother was the most significant factor that influenced the infant's antibody level. Vaccination of women before pregnancy could enhance passive antibody protection by increasing the level of transplacental transmission.