title: Prevalence of rubella-specific IgG antibodies in unimmunized young female population.
abstract: BACKGROUND
  Rubella is a mild self-limiting disease all over the world; nevertheless, it is of significant public health importance due to its teratogenic effect of congenital rubella syndrome. Rubella vaccine is currently not included in the national immunization program in India. Rubella-specific IgG in the unvaccinated population is a marker of previous rubella infection. Rubella IgG estimation in children will provide data for initiation and necessary modification to the immunization strategy.
  
  
  OBJECTIVE
  In this background, this study was conducted with an aim to know the age-specific susceptibility of acquiring rubella infections and future risk of congenital rubella syndrome (CRS) among girls.
  
  
  METHODS
  This was a community-based, observational study.
  
  
  METHODS
  The study was conducted at a randomly selected rural area Mavoor Panchayath of Kozhikode District, Kerala, among adolescent girls. The estimation of rubella-specific IgG antibody was done by quantitative enzyme-linked immunosorbent assay method. IgG titer value of >15 IU was taken positive, 8-15 IU as equivocal, and <8 IU as negative.
  
  
  METHODS
  Statistical analysis was performed using Statistical program for Social science version 16 for Windows. Chi-square test was applied to find out significant difference and Fisher's exact test wherever applicable.
  
  
  RESULTS
  The data and blood sample collection was done from 250 girls. The mean IgG titer was 151.93 ± 128.78 IU, and as per the criteria, 68.3% were positive, 28.5% were negative, and 3.2% were equivocal. At this age, majority (68.3%) of the girls get protection by natural infection without any vaccine. Some girls (32%) may remain susceptible to infection during adulthood and pregnancy.
  
  
  CONCLUSIONS
  Natural rubella infection was widely prevalent among child population and at this age. An immunization policy recommending rubella-containing vaccine is highly desirable to prevent rubella and CRS.
authors.affiliation: Department of Community Medicine, Government Medical College, Calicut, Kerala, India.
authors.forename: Jayakrishnan
authors.initials: J
authors.lastname: Thayyil
authors.affiliation: Apartment 206, 10300 W, Blue Mount Road, Wisconsin, USA.
authors.forename: Vidya
authors.initials: V
authors.lastname: Kuniyil
authors.affiliation: Department of Microbiology, Government Medical College, Calicut, Kerala, India.
authors.forename: Anitha P
authors.initials: AP
authors.lastname: Moorkoth
authors.affiliation: Department of Community Medicine, Government Medical College, Calicut, Kerala, India.
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Rao
authors.affiliation: Department of Community Medicine, KAP Viswanathan Government Medical College, Trichy, Tamil Nadu, India.
authors.forename: Paramasivam
authors.initials: P
authors.lastname: Selvam
keywords: Age shifting; congenital rubella syndrome; herd immunity; immunization policy; rubella-specific immunity