Rubella seroprevalence in an unvaccinated pregnant population in Malatya, Turkey

Summary 

Background: Controlling congenital rubella by 2010 is one of the targets of the World Health Organization. Most European countries currently include rubella vaccine in their national immunization programmes, but not yet in Turkey.

Objectives: To define rubella seroprevalence in pregnancy in Malatya, Turkey.

Study design: A cross-sectional interview survey was conducted among pregnant women living in Malatya province from November 2003 to May 2004, together with a follow-up component.

Methods: Stratified probability proportional to size sampling methodology. A total of 824 pregnant women from 60 clusters were enrolled. After obtaining informed consent, participants’ socio-demographic and fertility characteristics were collected by interview questionnaire. Various blood samples were drawn. After storing serum samples at −20°C for 6 months, anti-rubella IgM and IgG titres were studied by micro ELISA. Only 803 sera were eligible for serological study.

Results: Of the 803 samples tested for rubella antibodies, 753 cases (93.8%) had anti-rubella IgG positivity, indicating past infection. Five of the pregnant women (0.6%) had both anti-rubella IgM and IgG positive results, suggesting a recent infection. The remaining 45 women (5.6%) were seronegative for both antibodies. Seroprevalence was not associated with age or urban/rural residency. All the five anti-rubella IgM positive women were in the second trimester of pregnancy.

Conclusions: As 5.6% of pregnant women were susceptible to rubella during pregnancy, and five of them had already had a recent infection, immunization efforts should be directed at babies and adolescents.

Keywords: Rubella seroprevalence, Anti-rubella IgG, Pregnant women