Rubella is now very rare because of widespread compliance with childhood immunization programs.
The disease usually is a benign and inconsequential viral illness unless exposure occurs in utero. Congenital rubella syndrome is associated with significant congenital malformations. The live-attenuated virus vaccine has significantly decreased the incidence of rubella, thereby decreasing congenital disease. The causative organism is a single-stranded RNA togavirus, which is transmitted via respiratory droplets. The virus replicates in the nasopharynx and regional lymph nodes, resulting in viremia.