ANTIBODY-RESPONSE TO MEASLES MUMPS RUBELLA VACCINE OF CHILDREN WITH MILD ILLNESS AT THE TIME OF VACCINATION

Objective.-To examine the response to measles-mumps-rubella (MMR) vacc ine among children with and without mild illness. Design.-Prospective cohort. Participants.-A total of 386 children aged 15 to 23 months. Ma in Outcome Measures.-Seroconversion rates to measles, mumps, and rubel la in ill and well children. Setting.-Six public health immunization c linics in two counties in the greater metropolitan Atlanta, Ga, area f rom February 1992 to April 1993. Results.-Acute upper respiratory trac t infection, otitis media, and diarrhea were observed in 128 (33%), 41 (11%), and 13 (3%) of the children (groups are not mutually exclusive ); 157 children had one of these mild illnesses and 229 were well. Ove rall seroconversion rates were 98% for measles, 83% for mumps, and 98% for rubella antigens, Measles seroconversion rates for ill children c ompared with well children, respectively, were as follows: upper respi ratory tract infection, 99% vs 97%; mild fever, 98% vs 97%; otitis med ia, 98% vs 98%; diarrhea, 100% vs 98%; and any mild illness, 99% vs 97 %. Estimates of the magnitude of antibody response to measles, mumps, and rubella antigens were the same for children with and without mild illness. There was no association of mild illness with increased rates and severity of adverse events reported in the 2 weeks after vaccinat ion. Conclusions.-Vaccinating children who present with mild illnesses with MMR vaccine is a safe and efficacious practice. These results su pport recommendations of the Advisory Committee on Immunization Practi ces and the American Academy of Pediatrics.