Measles vaccine; risk factors for low antibody titers before and after single dose

ABSTRACT

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. 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. 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. Measles immunization produces adequate immunological responses even among malnourished children however a second dose is necessary to increase the efficacy more than 95%