Rubella
Rubella is a mild, droplet-spread togaviral illness in children and adults, notable mainly for its potential to cause severe congenital rubella syndrome when primary infection occurs in an unimmunized pregnant woman. Diagnosis is by rubella-specific IgM/IgG or polymerase chain reaction (PCR), treatment is supportive, and prevention is the measles-mumps-rubella (MMR) vaccine plus preconception immunity screening.
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What this article covers
- Overview
Rubella ("German measles" or "3-day measles") is a mild, self-limited exanthematous illness in immunocompetent children and adults, caused by rubella virus, a togavirus, and spread by respiratory droplets.
- Epidemiology
Affects both children and young adults, unlike some exanthems concentrated in infancy.
- Risk factors
Lack of MMR vaccination or documented immunity is the dominant risk factor for acquiring rubella.
- Pathophysiology
Rubella virus is a single-stranded RNA togavirus that enters via the respiratory mucosa and replicates in respiratory epithelium and regional lymph nodes before viremic spread.
- Clinical features
In postnatal (acquired) rubella, a mild prodrome precedes the rash and is milder than the prodrome of measles: low-grade fever, malaise, and upper respiratory symptoms, in contrast to the higher…
- Differential diagnosis
Measles: a higher, more sustained fever with a toxic-appearing prodrome (cough, coryza, conjunctivitis), Koplik spots, and a confluent, cephalocaudally spreading rash that appears while the fever is…
- Diagnosis
Rubella is confirmed by rubella-specific IgM and IgG serology, which are the best initial tests, with detection of rubella virus RNA by polymerase chain reaction (PCR) serving as the most accurate…
- Management
First, for typical postnatal rubella in a child or nonpregnant adult, treatment is entirely supportive, since no antiviral therapy targets rubella virus; the priority is symptom control and isolation, not antimicrobial therapy.
- Complications
Congenital rubella syndrome is the most serious complication, occurring when primary maternal infection happens in a nonimmune pregnant woman; risk of fetal damage is roughly 40 to 60% when infection…
- Prognosis
Excellent for postnatal rubella in immunocompetent, nonpregnant individuals, with full recovery expected within about a week.
- Prevention
The two-dose live attenuated MMR vaccine is the cornerstone of prevention, with routine childhood timing at 12 to 15 months and 4 to 6 years; adults born in or after 1957 without documented immunity…
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- Mumps
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- Vaccines
Vaccines are live attenuated, inactivated, subunit, conjugate, or toxoid preparations that induce antigen-specific active immunity to prevent infection or its complications before exposure occurs. Selection follows the age- and risk-based Advisory Committee on Immunization Practices schedule, with routine adult boosting such as Tdap every 10 years, and inactivated regimens substituted whenever a live vaccine is contraindicated by pregnancy or immunosuppression.