Cause: Rubella virus, a togavirus, genus Rubivirus.
Illness and treatment: Acquired rubella is usually mild with fever and a maculopapular rash moving down from the face to include the entire body. Up to 50% of infections are inapparent. Older children and adults may have malaise, lymph node swelling, and upper respiratory symptoms before the rash. Arthritis and arthralgia are frequent in adults. Complications including encephalitis (1 in 6000 cases) are uncommon and occur more often in adults. Congenital rubella syndrome (CRS) can result if a woman acquires rubella during pregnancy, especially in the first trimester. The virus may cause a variety of congenital malformations, most commonly deafness. Fetal death, spontaneous abortion, or premature delivery may occur.
Sources: Humans are the reservoir. Infants with CRS can shed virus for an extended period, but a true carrier state does not occur. Transmission is through airborne or droplet spread of the respiratory secretions of infected persons, including asymptomatic and subclinical infections.
Additional risks: Since 2004, rubella is no longer endemic in the United States. Most reported rubella cases in the country are now among Hispanic adults born in areas where rubella vaccine is not routinely used or infants of Hispanic women who were themselves born outside the United States. Adults are more likely than children to have encephalitis or develop arthritis.
Prevention: Universal childhood immunization prevents infection. Respiratory and hand hygiene can prevent transmission.
Recent Washington trends: In 2000, an infant with CRS was born in Washington to a Hispanic mother born outside the United States. This was the only CRS case reported in the state in the past 20 years. Since 2000 only 0 to 2 cases of acquired rubella have been reported annually.
Purpose of Reporting and Surveillance
- To prevent congenital rubella syndrome (CRS)
- To assure that children with suspected CRS are tested to confirm or rule out the diagnosis in a timely manner in order to assure prompt treatment and prevent spread of the disease.
- To assure that acquired rubella cases are tested to confirm or rule out the diagnosis. (As part of the proposed Healthy People 2010 objectives, a goal was established to eliminate U.S.-acquired rubella and CRS in the United States by the year 2010).
- To identify exposed pregnant women in a timely manner, determine their susceptibility and infection status, and provide appropriate counseling about the risk of fetal infection.
- To evaluate the effectiveness of disease prevention efforts such as immunization.
Legal Reporting Requirements
- Health care providers: immediately notifiable to local health jurisdiction
- Health care facilities: immediately notifiable to local health jurisdiction
- Laboratories: no reporting requirements
- Local health jurisdictions: notifiable to the Washington State Department of Health (DOH) Communicable Disease Epidemiology (CDE) within 7 days of case investigation completion or summary information required within 21 days