[Vaccination against epidemic parotitis].

Parotitis is usually a mild illness infrequently associated with severe complications, such as encephalitis, deafness or orchitis. The early studies of mumps vaccine (1940-1950) led to the development of killed virus preparations, which offered quite weakly protective immunity. Subsequently, attenuated live virus vaccines became available. These vaccines are more immunogenic and can be used mixed with measles and rubella vaccines. The widespread use of mumps vaccine in the United States has caused a dramatic reduction of the disease, with concomitant decrease of its complications. Although this may be explained by the vaccine-induced seroconversion (in over 95% of cases), the duration of protection is still unclear, since it is theoretically possible that after mumps immunization the infection could occur in older age-groups.