Rubella

The rubella virus is a type of togavirus belonging to genus Rubivirus. The virus core contains single-stranded RNA (ribonucleic acid) and is surrounded by an envelope. The rubella virus can be inactivated by ultraviolet light, acidic environments, heat, lipid solvents, trypsin, formalin, and amantadine.¹

Moderately contagious, rubella virus transmission occurs via droplets that are shed from respiratory secretions from an infected person to a susceptible individual. The rubella virus can spread when an infected person coughs or sneezes and droplets go to a noninfected person.^1,2,3

Once a person is infected, the virus replicates in the nasopharynx and regional lymph nodes and then spreads throughout the body.¹

In pregnant women, transplacental infection of the fetus can occur during this time, leading to fetal damage.^1,2

A person infected with rubella can be particularly contagious up to 1 week before a rash appears and up to 7 days after the appearance of a rash. However, some may not develop a rash or have any symptoms.^1,3

Those who are aware of their infection need to inform coworkers, classmates, teachers, daycare staff, friends, and family, and especially women who are pregnant.³

Infants with congenital rubella syndrome (contracted during fetal exposure) can transmit rubella to those around them as they tend to shed large quantities of the virus from body secretions for up to 1 year.¹

“Rubella” in Latin refers to “little red” as it was first considered in the early 1800s to be a variant of measles or scarlet fever. It was referred to as “third disease”. In 1814, German medical literature started to describe it as a separate disease. From then on, it was commonly known as “German measles”.¹

As with most viral infections, pathogenesis and clinical features usually present in phases: incubation phase, viremia phase, and prodromal phase.

General Clinical Phases of the Rubella Infection¹

Severe rubella complication occurs when a fetus is infected as a result of maternal exposure, also known as congenital rubella syndrome (rubella pregnancy complications).¹

Long-term Concerns of Congenital Rubella Syndrome¹

• Severity dependent on time of gestation during infection
  • Most severe when infected early in gestation (≤20 weeks of gestation)
  • Rare defects when infected late in gestation (>20 weeks of gestation)
• May affect all organs and cause a variety of congenital defects:
  • Deafness (most common, may often be the only manifestation)
  • Eye defects
  • Cardiac defects
  • Neurologic abnormalities
  • Bone lesions
  • Enlarged spleen
  • Hepatitis
  • Excessive bruising or bleeding
• Various manifestations may have a delayed onset of 2–4 years or more:
  • Diabetes mellitus in later childhood
  • Progressive encephalopathy
  • Autism
• Reinfection may occur

Other complications in the general population as a result of rubella infection can vary depending on age and gender.¹

Other Complications, Dependent on Age and Gender

Since rubella infection can appear similar to other rash illnesses or may be asymptomatic, a positive viral culture is needed to make a positive rubella diagnosis. Virus can be isolated from nasal, blood, throat, urine, and cerebrospinal fluid samples of rubella and congenital rubella syndrome patients. Laboratory confirmation of the rubella virus is helpful for epidemiologic purposes.¹