Infectious agent: The rubella virus is a togavirus, genus Rubivirus.
Mode of transmission: Direct or droplet contact with nasopharyngeal secretions of an infected person.
Period of Communicability: The infectious period is considered to be from 7 days before onset of rash to 7 days after the onset of rash, possibly up to 14 days after onset of rash. Infants with Congenital Rubella Syndrome (CRS) may shed virus in nasopharyngeal secretions and urine up to a year after birth.
CDC Case Definition and Classification (for purposes of public health reporting) Clinical Case Definition
An illness with all of the following characteristics:
Acute onset of generalized maculopapular rash AND
Temperature greater than 37.2ºC (99ºF), if measured AND
Arthralgia/arthritis, or lymphadenopathy, or conjunctivitis
Laboratory Criteria for Diagnosis
Laboratory confirmation is obtained from a single serum specimen drawn 2-28 days after rash onset
which contains rubella IgM antibody
A significant rise in rubella IgG antibody in paired acute and convalescent sera drawn 14 days apart (3
weeks apart for an exposed person who does not develop a rash illness)
Specimens to Collect
When investigating a suspect rubella, collect the following specimens:
Acute and convalescent sera (collect acute specimen as soon as possible after rash onset and no later than 7 days post rash onset; collect convalescent specimen >= 2 weeks after the acute specimen was collected),
Nasopharyngeal swab in Hank’s solution (no later than 5 days post rash onset) – (See “Instructions for Collecting Nasopharyngeal Swab Specimens” document).
Thirty to 50% of rubella infections are asymptomatic.
The incubation period varies from 14-23 days, but usually 16-18 days.
In older children and adults, occurs 1-5 days before onset of rash. Symptoms are often mild, including low grade fever, malaise, swollen glands and upper respiratory infection symptoms.
Initially occurs on the face and progresses from head to feet, being less evident on extremities than on face and trunk. Fainter than measles rash, usually does not coalesce and is occasionally itchy. Lasts about 3 days.
Arthralgia (achy joints)
Occurs at the same time or shortly after rash. Occurs in 70% of adult women but rarely in adult males or children.
Recommended Treatment and Chemoprophylaxis
Treatment of rubella is supportive. Neither rubella vaccine nor IG is effective for post exposure prophylaxis.
Proof of rubella immunity is determined by meeting one of the following criteria:
1. Documentation of having received one dose of live virus rubella vaccine on or after 12 months of age
2. Serological evidence of rubella antibody
Rubella is a reportable disease, and County or Local Health Departments must be notified within 24 hours when a case of rubella is suspected. A Rash Illness Investigation Form and Communicable Disease Reporting Form must be submitted for each suspected and confirmed rubella case. Complete a Congenital Rubella Syndrome Case Report for each case of congenital rubella. Reporting of communicable disease is mandated under the Arizona Administrative Codes (R9-6-352). Investigation checklist:
1. Upon notification of a suspected rubella case, complete Rash Illness Investigation Form and Communicable Disease Reporting Form by conducting an interview with the rubella case to:
obtain patient information (at a minimum: name, age, address and type of setting exposed)
obtain information regarding clinical signs and symptoms
collect all pertinent medical information (recent medications, physician information, hospitalization, etc.)
determine patient's immune status (history of rubella vaccination or serological evidence of rubella antibody).
determine the possible source of exposure, such as: