The rubella virus is an RNA togavirus.11 The primary site of infection is the respiratory epithelium of the nasopharynx. The virus is spread primarily by droplets generated during talking, breathing, coughing, and sneezing; by direct contact with nasal or throat secretions; and less frequently by touching freshly contaminated articles and environmental surfaces. The period of maximal communicability extends from a few days before to 7 days after the onset of rash.
Signs and symptoms of German measles typically appear 14 days (range of 12 to 23 days) after exposure to the rubella virus. Most infections are subclinical. When symptomatic, rubella is characterized by acute onset of generalized maculopapular rash, which first appears on the face and spreads rapidly to the trunk and limbs; fever ≥99.0°F (≥37.2°C); arthralgia and arthritis, particularly in postpubertal females; lymphadenopathy; and conjunctivitis.
Rubella is a vaccine-preventable disease and rubella infection confers life-long immunity. In the absence of acceptable presumptive evidence of immunity, active immunization is highly recommended. Prevaccination antibody testing before vaccination of HCP is not necessary. While separate monovalent formulation vaccines for measles, mumps, and rubella are available, the trivalent MMR vaccine is the vaccine of choice for routine adult vaccination.
There is no specific antiviral therapy for rubella. Medical care is supportive to help relieve symptoms and to address complications such as bacterial infections. There is no evidence that postexposure vaccination is effective in preventing rubella infection. In the absence of acceptable presumptive evidence of immunity the administration of immunoglobulin within 72 hours of rubella exposure might reduce (but not eliminate) the risk of infection.