General trends and specifics of the unified epidemiological surveillance system, and activities at different stages of measles and rubella control in Leningrad oblast
Published: 29.07.10 Updated: 24.08.2010 16:03:07
Editorial Office apologises for the missed publication of the abstract by E. Mikhaylova at the Regional Epidemiologists’ Meeting in Minsk, Republic of Belarus, in 2009. The abstract is published below. Other abstracts of the meeting are published in EpiNorth, 2009,10(3):140-56.
Directorate of the Federal Service for Surveillance on Consumer Rights Protection and Human Well-being (Rospotrebnadzor) in Leningrad oblast, Saint-Petersburg, Russia
Citation: Mikhailova E. General trends and specifi cs of the unifi ed epidemiological surveillance system, and activities at diff erent stages of measles and rubella control in Leningrad oblast.EpiNorth 2010;11:27-8.
Official registration of rubella infection in Russia started in the 1980s. Rubella incidence is of especial interest among pregnant women, who constitute a risk group, due to the teratogenic effects of rubella virus infection that causes congenital rubella syndrome (CRS) in newborns.
As in other regions of Russia, rubella remained uncontrollable in Leningrad oblast up to 1999 prior to the availability of a specifi c vaccine and the infection followed a natural epidemic course. During the pre-vaccination period, the rubella epidemic process proceeded rather actively and was characterised by a high incidence rate. Since the introduction of mandatory vaccination, the incidence rate in Leningrad oblast during 2001-2006 accounted for an average of 600 cases per year; revaccination since 2007 has decreased the incidence to 300 cases per year. In the fi rst half of 2009, 13 cases of rubella infection were reported. A high incidence rate and primary epidemiological factors of rubella infection (frequency, seasonality, etc.) are mainly associated with children. The highest rubella incidence rate is registered among children aged 3-14 years. The mass immunisation of children and women that was conducted in Leningrad oblast as part of the National Priority Project in Public Health in 2006-2007 raised the vaccination coverage to the recommended level (95% and higher). The incidence rate decreased and the natural reservoir of rubella virus and risk of infection among women of childbearing age was signifi cantly reduced. Although the problem of congenital rubella is socially and medically signifi cant, mandatory reporting and recording of CRS has not been introduced in Leningrad oblast to
Up to 20% of pregnant women are found to be seronegative for rubella which indicates a high risk of congenital pathology in newborns. Of 129 pregnant women in Leningrad oblast who were examined for rubella virus-specific antibodies in blood, 5.4% were seronegative for rubella virus. Every year approximately 2% of children are born with various birth defects in Leningrad oblast. Children born in 2005-2008 (835 children) had birth defects associated with CRS including heart defects (25% of cases), cataracts (2 cases), central nervous system defects (4% of cases), deafness (3 cases) and digestive and urogenital system abnormalities (20% of cases).
At present, the primary objective is to organise the epidemiological and immunological surveillance of rubella infection in order to prevent infection among pregnant women and the occurrence of CRS. In addition, a number of important issues may be resolved as part of epidemiological surveillance for rubella infection including:
- Establishment of comprehensive recording and notifi cation of all rubella cases;
- Determination of rubella incidence rate among pregnant women as well as the incidence and nature of rubella related-congenital pathology in newborns;Identifi cation of high-risk groups that require additional attention regarding improvement of specific immunity.
- Identifi cation of high-risk groups that require additional attention regarding improvement of specific immunity.