Seroprevalence of Measles, Mumps and Rubella Antibodies in 18 Months and 6.5 Years Old Children: Six Months After Measles-Mumps-Rubella (MMR) Vaccination

Background: Mumps, measles and rubella viruses lead to various kinds of complications such as meningoencephalitis, deafness, congenital abnormalities and even cause mortality in malnourished patients,. Since 2004, MMR vaccination in two series of one year of age and four to six years has been administered to Iranian children as a part of routine vaccination program. Recently, MMR vaccination schedule has been changed to one year and 18 months series. Objectives: Since MMR vaccine has been recently entered childhood vaccination program, this study was performed to determine immunity response against mumps, measles and rubella six months after one year and four to six years of age vaccination. Patients and Methods: In a cross-sectional study, antibody titers after MMR vaccination at 18 months (six months after dose of one year) in 70 children, and at 6.5 years (six month after dose of six years) in 90 children referred to Ahvaz Abuzar Children’s Hospital Vaccination Clinic during 2007-2008 were detected by ELISA method. Results: In 70 children (34 boys and 36 girls) who were vaccinated at one year, 30 (42.9 %) had antibody against measles, 63 (90 %) against rubella and 41 (58.6 %) against mumps. In 90 children (54 boys and 36 girls at 6.5 years of age (six months after vaccination), 41 (45.6%) children had antibody against measles, 79 (87.8 %) against rubella and 69 (76.7%) against mumps. Conclusions: the results of this study showed that after MMR vaccination, the level of antibody for measles was about 45 % and for mumps about 50-80 %. This level of immunity is not acceptable for successful vaccination. while the level of antibody against rubella was sufficient. For better evaluation of MMR vaccination, further studies and from other parts of the country is needed.