Measles, Mumps, and Rubella - Centers for Disease Control and ...

6 MMWR May 22, 1998that had elapsed since they were initially vaccinated. However, recent rubella surveillancedata do not indicate that rubella and CRS are increasing among vaccinatedpersons (28 ) (CDC, unpublished data).The primary objective of the rubella immunization program is the prevention ofCRS. The major components of the rubella and CRS elimination strategy are achievingand maintaining high immunization levels for children and adults, especially womenof childbearing age; conducting accurate surveillance for rubella and CRS; and undertakingcontrol measures promptly when a rubella outbreak occurs. Since the late1970s, this strategy has effectively prevented major epidemics of rubella and CRS inthe United States.MumpsClinical CharacteristicsPersons in whom “classical” mumps develops have bilateral or (less commonly)unilateral parotitis, with onset an average of 16–18 days after exposure. Parotitis maybe preceded by fever, headache, malaise, myalgia, and anorexia. Only 30%–40% ofmumps infections produce typical acute parotitis; 15%–20% of infections are asymptomaticand up to 50% of infections are associated with nonspecific or primarilyrespiratory symptoms (29,30 ). Inapparent infection may be more common amongadults than children; parotitis occurs more commonly among children aged 2–9 years(30,31 ). Serious complications of mumps infection can occur without evidence ofparotitis (29,32,33 ).Most serious complications of mumps are more common among adults thanamong children (29,34 ). Although orchitis may occur among up to 38% of postpubertalmen in whom mumps develops, sterility is thought to occur only rarely (35 ).Aseptic meningitis affects 4%–6% of persons with clinical cases of mumps and typicallyis mild (29,36–38 ). However, mumps meningoencephalitis can cause permanentsequelae, including paralysis, seizures, cranial nerve palsies, aqueductal stenosis, andhydrocephalus (39–41 ). In the prevaccine era, mumps was a major cause of sensorineuraldeafness among children. Deafness may be sudden in onset, bilateral, andpermanent (42–44 ).Among women in whom mumps develops during the first trimester of pregnancy,an increased risk for fetal death has been observed (45 ). However, mumps infectionduring pregnancy is not associated with congenital malformations (46 ).Mumps ControlIn the United States, the reported incidence of mumps decreased steadily after theintroduction of live mumps vaccine in 1967 and the recommendation for its routineuse in 1977. In 1995, 906 cases were reported, representing a 99% decrease from the185,691 cases reported in 1968. The enactment and enforcement of state vaccinationlaws requiring that students be vaccinated before school entry has contributed moreto reducing mumps incidence than any other measure (47 ). During the 1980s andearly 1990s, mumps incidence was lowest in states where comprehensive vaccinationlaws were enforced. States where vaccination laws were less comprehensive reported