| Disease factor |
| Highest number of U.S. cases | 894,134 cases in 194117 | 152,209 cases in 196818 | 12 million cases in 1964–1965; 57,686 cases in 196919 | Highly efficacious in preventing disease† |
| Congenital rubella: 20,000 cases in 1964–196519 |
| Recent number of U.S. cases | 86 cases in 200020 | 338 cases in 200020 | 176 cases in 200020 | No cases of congenital rubella reported after immunization of pregnant women, but theoretic risk is 2%21 |
| Congenital rubella: 9 cases in 200020 |
| Transmission route | Droplets | Direct contact, airborne droplets, fomites by saliva | Oral droplets | — |
| Congenital rubella: transplacental passage |
| Transmission risk in susceptible household contacts | 90% in susceptible household contacts17 | Rate not available, because 30% to 40% of infections are subclinical18 | 50% to 60% in susceptible family members and almost 100% in closed populations19 | — |
| Incidence of defects in congenital rubella: 50% with infection during first month of pregnancy; 20% to 30% with infection during second month; 5% with infection during third or fourth month11(pp495–500) |
| Risk of sequelae |
| Mortality | 1 to 2 deaths per 1,000 measles cases11(pp385–96),17 | 2.5 to 50 deaths per 1 million mumps cases, because of 1.4% to 2% fatality rate from encephalitis18,22 | 1 death per 30,000 rubella cases, because of 20% fatality rate from encephalitis19 | 1 death, but not attributed to vaccine14 |
| Fatal measles pneumonitis in a 21-year-old man with advanced HIV infection23 |
| Congenital rubella: no data available |
| Encephalitis | 1 to 2 cases per 1,000 measles cases17 | 1 case per 400 to 6,000 mumps cases22 | 1 case per 5,000 to 6,000 rubella cases19 | 1 case per 1 million doses14 |
| Subacute sclerosing panencephalitis | 8.5 cases per 1 million measles cases17 | — | 20 reported cases of progressive rubella panencephalitis19 | 0 to 0.7 cases per 1 million doses14,17 |
| Pneumonia | 3% of young adults with measles23 | — | — | 2 cases per 1 million doses14 |
| Thrombocytopenia | | Rare22 | 1 case per 3,000 rubella cases19 | 0.5 to 33 cases per 1 million doses11(pp385–96),14 |
| Orchitis | — | 14% to 35% of adolescent and adult men with mumps14,18 | — | 0.3 cases per 1 million doses14 |
| Anaphylaxis | — | — | — | 5 cases per 1 million doses (none fatal)14 |