Rubella

Rubella
Other namesGerman measles, three-day-measles
Rash of rubella on back (crop).JPG
A rash due to rubella on a child's back. The area affected is similar to that of measles but the rash is less intensely red.
SpecialtyInfectious disease
SymptomsRash, swollen lymph nodes, fever, sore throat, feeling tired[1][2]
ComplicationsTesticular swelling, inflammation of nerves, congenital rubella syndrome, miscarriage[1][3]
Usual onset2 weeks after exposure[1]
Duration3 days[1]
CausesRubella virus (spread through the air)[3][4]
Diagnostic methodFinding the virus in the blood, throat, or urine, antibody tests[1]
PreventionRubella vaccine[3]
TreatmentSupportive care[2]
FrequencyCommon in many areas[2]

Rubella, also known as German measles or three-day measles,[5] is an infection caused by the rubella virus.[3] This disease is often mild with half of people not realizing that they are infected.[1][6] A rash may start around two weeks after exposure and last for three days.[1] It usually starts on the face and spreads to the rest of the body.[1] The rash is sometimes itchy and is not as bright as that of measles.[1] Swollen lymph nodes are common and may last a few weeks.[1] A fever, sore throat, and fatigue may also occur.[1][2] In adults joint pain is common.[1] Complications may include bleeding problems, testicular swelling, and inflammation of nerves.[1] Infection during early pregnancy may result in a child born with congenital rubella syndrome (CRS) or miscarriage.[3] Symptoms of CRS include problems with the eyes such as cataracts, ears such as deafness, heart, and brain.[3] Problems are rare after the 20th week of pregnancy.[3]

Rubella is usually spread through the air via coughs of people who are infected.[3][4] People are infectious during the week before and after the appearance of the rash.[1] Babies with CRS may spread the virus for more than a year.[1] Only humans are infected.[3] Insects do not spread the disease.[1] Once recovered, people are immune to future infections.[3] Testing is available that can verify immunity.[3] Diagnosis is confirmed by finding the virus in the blood, throat, or urine.[1] Testing the blood for antibodies may also be useful.[1]

Rubella is preventable with the rubella vaccine with a single dose being more than 95% effective.[3] Often it is given in combination with the measles vaccine and mumps vaccine, known as the MMR vaccine.[1] When some, but less than 80%, of a population is vaccinated, more women may reach childbearing age without developing immunity by infection or vaccination, thus possibly raising CRS rates.[3] Once infected there is no specific treatment.[2]

Rubella is a common infection in many areas of the world.[2] Each year about 100,000 cases of congenital rubella syndrome occur.[3] Rates of disease have decreased in many areas as a result of vaccination.[2][6] There are ongoing efforts to eliminate the disease globally.[3] In April 2015 the World Health Organization declared the Americas free of rubella transmission.[7][8] The name "rubella" is from Latin and means little red.[1] It was first described as a separate disease by German physicians in 1814 resulting in the name "German measles".[1]

Signs and symptoms

Young boy displaying the characteristic maculopapular rash of rubella[9]
Generalized rash on the abdomen due to rubella

Rubella has symptoms that are similar to those of flu. However, the primary symptom of rubella virus infection is the appearance of a rash (exanthem) on the face which spreads to the trunk and limbs and usually fades after three days (that is why it is often referred to as three-day measles). The facial rash usually clears as it spreads to other parts of the body. Other symptoms include low grade fever, swollen glands (sub-occipital and posterior cervical lymphadenopathy), joint pains, headache, and conjunctivitis.[10]

The swollen glands or lymph nodes can persist for up to a week and the fever rarely rises above 38 °C (100.4 °F). The rash of German measles is typically pink or light red. The rash causes itching and often lasts for about three days. The rash disappears after a few days with no staining or peeling of the skin. When the rash clears up, the skin might shed in very small flakes where the rash covered it. Forchheimer's sign occurs in 20% of cases, and is characterized by small, red papules on the area of the soft palate.[11]

Rubella can affect anyone of any age. Adult women are particularly prone to arthritis and joint pains.[12]

In children rubella normally causes symptoms which last two days and include:[13]

  • Rash beginning on the face which spreads to the rest of the body.
  • Low fever of less than 38.3 °C (101 °F).
  • Posterior cervical lymphadenopathy.[14]

In older children and adults additional symptoms may be present including:[13]

  • Swollen glands
  • Coryza (cold-like symptoms)
  • Aching joints (especially in young women)

Severe complications of rubella include:

Coryza in rubella may convert to pneumonia, either direct viral pneumonia or secondary bacterial pneumonia, and bronchitis (either viral bronchitis or secondary bacterial bronchitis).[16]

Congenital rubella syndrome

Cataracts due to congenital rubella syndrome

Rubella can cause congenital rubella syndrome in the newborn, the most severe sequela of rubella. The syndrome (CRS) follows intrauterine infection by the rubella virus and comprises cardiac, cerebral, ophthalmic and auditory defects.[17] It may also cause prematurity, low birth weight, and neonatal thrombocytopenia, anemia and hepatitis. The risk of major defects or organogenesis is highest for infection in the first trimester. CRS is the main reason a vaccine for rubella was developed.[18]

Many mothers who contract rubella within the first critical trimester either have a miscarriage or a stillborn baby. If the fetus survives the infection, it can be born with severe heart disorders (patent ductus arteriosus being the most common), blindness, deafness, or other life-threatening organ disorders. The skin manifestations are called "blueberry muffin lesions".[18] For these reasons, rubella is included on the TORCH complex of perinatal infections.

About 100,000 cases of this condition occur each year.[3]