Assessing Seropositivity of MMR Antibodies in Individuals Aged 2–22: Evaluating Routine Vaccination Effectiveness after the 2003 Mass Campaign-a Study from Iran’s National Measles Laboratory

The seroprevalence of antibodies against measles, mumps, and rubella (MMR) was evaluated 17 years following a mass vaccination campaign in individuals aged 2 to 22 years who had received routine immunization but were not eligible for an extended immunization program. Samples were acquired from Iran’s National Measles Laboratory (NML), with individuals showing positive IgM results excluded. Out of the samples collected in 2020, a random selection of 290 serum samples was chosen, representing individuals between the ages of 2 and 22 years from diverse regions in the country. These samples were subjected to analysis using an enzyme-linked immunosorbent assay (ELISA) to quantify specific IgG antibodies against MMR. The seroprevalence rates of antibodies for measles, mumps, and rubella were determined to be 76.2