Risk Factors for Low Antibody Titers before and after Single Dose

.. Objective: To determine the rate of sero-conversion after first dose of measles immunization in children less than one year of age and to find out association between seroconversion with nutritional status, URTI, fever and diarrhea. Methodology: Descriptive cross sectional study of 6 month duration conducted at outpatient department, EPI center LUH Hyderabad. Total 240 children between 9 to 12 months, who came for measles immunization were enrolled. Pre-vaccination blood samples were obtained along with assessment of nutritional status, and current associated illness like pneumonia, diarrhea and fever of each child. The post vaccination samples were taken after 3 months. Measles antibodies were estimated by using ELISA technique and titers were compared with controls supplied by manufacturers. Results: The effectiveness of measles immunization was 87.5%. Statistical analysis proved that association sero-negativity with clinical condition was insignificant (Chi square test, P value > 0.05). Regarding the pre-vaccinated status 222 (92.5%) were found negative for anti-measles antibodies and 18 (7.5%) were found to be with persistent maternal anti-measles antibodies. Conclusions: Measles immunization produces adequate immunological responses even among malnourished children however a second dose is necessary to increase the efficacy more than 95%.