Immune status of health care personnel & post vaccination analysis of immunity against rubella in an eye hospital.

BACKGROUND & OBJECTIVES Congenital rubella syndrome (CRS) accounts for a significant amount of mortality and morbidity in India. Rubella vaccination is not included in our national immunization programme. Occupational exposure of the health care personnel to rubella infection is well known. This study aims to assess the serological status of health care workers against rubella virus in Aravind Eye Care System, Madurai and to follow the immune response in the seronegative individuals after vaccination. METHODS A total of 500 female and 81 male workers were enrolled in the study. Blood sample was collected for the analysis of rubella specific IgM and IgG antibodies. The seronegative individuals were vaccinated with monovalent rubella vaccine, RA 27/3. The post-vaccination samples were analysed for the antibody levels and their avidity using enzyme immunoassay. RESULTS Of the 581 volunteers, 493 were seropositive with good protective immunity and 22 had both IgM and IgG antibodies. Sixty six volunteers (59 females and 7 males) were found to be seronegative to rubella. The seroconversion was observed in all the sixty vaccinated individuals, as seen by the appearance of anti-rubella IgG antibodies by fourth week, reaching the peak protective levels (>20 IU/ml) by third month. There was also a progressive increase in the avidity after vaccination. INTERPRETATION & CONCLUSION Nearly 11.4 per cent of the health care workers were found to be seronegative for rubella virus and after vaccination, these volunteers developed a good protective immunity, thereby reducing the risk of contracting the hospital based rubella infection. Therefore, rubella vaccination may be instituted in hospitals for the benefit of health care workers.