Long-term Seroprotection Rates Following Second Dose of Measles as MMR Vaccine at 15 months in Indian Children

Objective: To find out seropositivity rates at 4-6 and 9-12 years of age; among those whoreceived one-dose measles at 9 months and one-dose MMR at 15 months of age. Methods:80 healthy children (53 males) at 4-6 or 9-12 years of age, attending outpatient departmentfor vaccination were enrolled. Antibody titers were estimated using commercially availablequantitative-IgG ELISA kits. Results: The seropositivity rates against measles, mumps,rubella were 80% (40/50), 86% (43/50), and 96% (48/50), respectively at 4-6 years, and83.3% (25/30), 96.7% (29/30) and 96.7% (29/30), respectively at 9-12 years of age.Conclusion: Single dose of rubella vaccine seems to provide adequate long-termprotection; however, measles vaccine requires more doses for similar protection.