Rubella in the Russian Federation: epidemiological features and control measures to prevent the congenital rubella syndrome.

A review of the epidemiology of clinical rubella in the Perm region of the Russian Federation from 1979-97 showed that the incidence was about 220 cases per 100,000 population. Congenital rubella syndrome (CRS) accounted for 15% of birth defects and for about 3.5 cases of CRS per 1000 live births per year. Surveys of the seroepidemiology of rubella infection revealed that the susceptibility rate among pregnant women (i.e. rubella virus antibody haemagglutination-inhibition (HAI) assay titres < 10) was 16.5%. As serum rubella antibody HAI titres > or = 10 both prevented infection in pregnant women and protected their foetuses, serological testing has been introduced into the routine antenatal services. Pre-existing rubella antibodies were found not to interfere with the immune response to vaccination, so selective immunization was provided to girls approaching puberty and to women of childbearing age. A programme of epidemiological surveillance is being developed to define tactics for the widescale introduction of rubella vaccination.