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Rubella

(German Measles; 3-Day Measles)

By

Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised May 2023
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Topic Resources

Rubella is a viral infection that may cause adenopathy, rash, and sometimes constitutional symptoms, which are usually mild and brief. Infection during early pregnancy can cause spontaneous abortion, stillbirth, or congenital defects. Diagnosis is usually clinical. Cases are reported to public health authorities. Treatment is usually unnecessary. Vaccination is effective for prevention.

Rubella is caused by an RNA virus, which is spread by respiratory droplets through close contact or through the air. Patients can transmit rubella from 7 days before a rash appears until 15 days after onset of the rash; the period of greatest risk is from a few days before the rash appears to 7 days after onset of the rash. Some patients are asymptomatic, but they can transmit the virus. Congenitally infected infants Congenital Rubella Congenital rubella is a viral infection acquired from the mother during pregnancy. Signs are multiple congenital anomalies that can result in fetal death. Diagnosis is by serology and viral... read more may transmit rubella for many months after birth.

Rubella is less contagious than measles Measles Measles is a highly contagious viral infection that is most common among children. It is characterized by fever, cough, coryza, conjunctivitis, an enanthem (Koplik spots) on the oral mucosa... read more Measles . Immunity appears to be lifelong after natural infection. However, in unvaccinated populations, 10 to 15% of young adults have not had childhood infection and are susceptible.

At present, incidence in the United States is extremely low because of routine childhood vaccination; all cases since 2004 have been imported.

Symptoms and Signs of Rubella

Many cases are mild. After a 14- to 21-day incubation period, a 1- to 5-day prodrome, usually consisting of low-grade fever, malaise, conjunctivitis, and lymphadenopathy, occurs in adults but may be minimal or absent in children.

Tender swelling of the suboccipital, postauricular, and posterior cervical nodes is characteristic.

There is pharyngeal injection at the onset.

The rash that develops subsequently is similar to that of measles but is less extensive and more evanescent; it is often the first sign in children. It begins on the face and neck and quickly spreads to the trunk and extremities. At onset, a blanching, macular erythema may appear, particularly on the face. On the 2nd day, the rash often becomes more scarlatiniform (pinpoint) with a reddish flush. Petechiae form on the soft palate (Forchheimer spots), later coalescing into a red blush. The rash lasts 3 to 5 days.

Constitutional symptoms in children are absent or mild and may include malaise and occasional arthralgias.

Adults usually have few or no constitutional symptoms but occasionally have fever, malaise, headache, stiff joints, transient arthritis, and mild rhinitis. Fever typically resolves by the 2nd day of the rash.

Encephalitis has occurred rarely during large military outbreaks. Complete resolution is typical, but encephalitis is occasionally fatal.

Thrombocytopenic purpura and otitis media occur rarely.

Diagnosis of Rubella

  • History and physical examination

  • Serologic testing

Rubella is suspected in patients with characteristic adenopathy and rash.

Laboratory diagnosis is necessary for pregnant women, patients with encephalitis, and neonates. Also, laboratory evaluation is strongly encouraged for all suspected cases of rubella for public health purposes. A 4-fold rise between acute and convalescent (4 to 8 weeks) antibody titers confirms the diagnosis, as can serum rubella IgM antibody testing.

Detection of viral RNA by reverse transcription–polymerase chain reaction testing of throat, nasal, or urine specimens may also be done to confirm the diagnosis; genotype analysis is useful in epidemiologic investigations.

Differential diagnosis includes measles Measles Measles is a highly contagious viral infection that is most common among children. It is characterized by fever, cough, coryza, conjunctivitis, an enanthem (Koplik spots) on the oral mucosa... read more Measles , scarlet fever Scarlet fever Streptococci are gram-positive aerobic organisms that cause many disorders, including pharyngitis, pneumonia, wound and skin infections, sepsis, and endocarditis. Symptoms vary with the organ... read more Scarlet fever , secondary syphilis Secondary syphilis Syphilis is caused by the spirochete Treponema pallidum and is characterized by 3 sequential symptomatic stages separated by periods of asymptomatic latent infection. Common manifestations... read more Secondary syphilis , drug rashes, erythema infectiosum Erythema Infectiosum (Parvovirus B19 Infection) Erythema infectiosum is caused by acute infection with human parvovirus B19. In children, it causes mild constitutional symptoms and a blotchy or maculopapular rash beginning on the cheeks and... read more Erythema Infectiosum (Parvovirus B19 Infection) , and infectious mononucleosis Infectious Mononucleosis Infectious mononucleosis is caused by Epstein-Barr virus (EBV, human herpesvirus type 4) and is characterized by fatigue, fever, pharyngitis, and lymphadenopathy. Fatigue may persist weeks or... read more Infectious Mononucleosis as well as echovirus Overview of Enterovirus Infections Enteroviruses, along with rhinoviruses (see Common Cold) and human parechoviruses, are a genus of picornaviruses (pico, or small, RNA viruses). All enteroviruses are antigenically heterogeneous... read more and coxsackievirus Overview of Enterovirus Infections Enteroviruses, along with rhinoviruses (see Common Cold) and human parechoviruses, are a genus of picornaviruses (pico, or small, RNA viruses). All enteroviruses are antigenically heterogeneous... read more infections (see table ). Infections with enteroviruses Overview of Enterovirus Infections Enteroviruses, along with rhinoviruses (see Common Cold) and human parechoviruses, are a genus of picornaviruses (pico, or small, RNA viruses). All enteroviruses are antigenically heterogeneous... read more and parvovirus B19 (erythema infectiosum) may be clinically indistinguishable.

Some of these conditions can be distinguished from rubella as follows:

  • Measles: Rubella is differentiated from measles by the milder, more evanescent rash, milder and briefer constitutional symptoms, and absence of Koplik spots, photophobia, and cough.

  • Scarlet fever: Within a day of onset, scarlet fever usually causes more severe constitutional symptoms and pharyngitis than does rubella.

  • Secondary syphilis: In secondary syphilis, adenopathy is not tender, and the rash is usually prominent on the palms and soles. Also, laboratory diagnosis of syphilis is usually readily available.

  • Infectious mononucleosis: Infectious mononucleosis can be differentiated by its more severe pharyngitis, more prolonged malaise, and atypical lymphocytosis and with Epstein-Barr virus antibody testing.

Treatment of Rubella

  • Supportive care

Treatment of rubella is symptomatic.

No specific therapy for encephalitis is available.

Prevention of Rubella

Two doses are recommended:

  • The first dose at age 12 to 15 months

  • The second dose at age 4 to 6 years

Infants immunized at < 1 year of age still require 2 additional doses given after their first birthday.

To prevent congenital rubella, unvaccinated patients who could become pregnant should receive one dose of the MMR vaccine and then wait 4 weeks before trying to conceive. For patients vaccinated during childhood, many clinicians do preconceptual serologic testing for rubella IgG to confirm immunity, because some people do not develop immunity after initial immunization. Once rubella immunity is confirmed, patients do not need to be tested again before subsequent pregnancies.

The vaccine causes mild or inapparent, noncommunicable infection. Fever > 38° C occurs 5 to 12 days after inoculation in 5 to 15% of vaccinees and can be followed by a rash. Central nervous system reactions are exceedingly rare. The MMR vaccine does not cause autism Measles-Mumps-Rubella (MMR) Vaccine Despite the rigorous vaccine safety systems in place in the United States, some parents remain concerned about the safety of the use and schedule of vaccines in children. These concerns have... read more .

MMR is a live vaccine and is contraindicated during pregnancy.

Prevention references

Key Points

  • Rubella causes a scarlatiniform rash and often low-grade fever, malaise, conjunctivitis, and lymphadenopathy (characteristically involving the suboccipital, postauricular, and posterior cervical nodes).

  • Most cases are mild and complications are few except for rare cases of encephalitis and the risk during early pregnancy that infection can cause spontaneous abortion, stillbirth, or congenital defects.

  • Laboratory diagnosis is strongly encouraged for all suspected cases for public health purposes; serologic or reverse transcription–polymerase chain reaction testing can be done.

  • Screen women of childbearing age for rubella antibodies and immunize those susceptible, providing conception is prevented for ≥ 28 days afterwards.

  • Vaccination is contraindicated during pregnancy.

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