1971 Volume 105 Issue 4 Pages 327-337
Epidemiological, clinical and serological studies on the epidemic mumps were carried out in 47 infants in Central Babies Home, Sapporo. Furthermore by utilizing fluorescent antibody tests the influence of transplacental maternal antibodies on mumps infection in infants was studied. The results obtained were as follows: 1) An epidemic of mumps was found to occur even in infants around 1 year of age, when the proportion of susceptibles in the population was high and when they were in close contact with each other. 2) Even the small amount of transplacental maternal antibodies, which were undetectable by hemagglutination inhibition or neutralizing tests, but detecta-ble only by fluorescent antibody tests, might protect mumps infection in infancy. 3) Fluorescent antibody tests were considered to be useful to determine whether the detected antibodies were due to natural mumps infection or of maternal origin: IgM mumps fluorescent antibody was specifically detected in the sera of those who received recent infection of mumps.