Rubella-Quick Sheet

Arizona Department of Health Services
*REPORT TO ADHS WITH 24 HOURS*

Rubella-Quick Sheet

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

The isolation of rubella virus from urine for strain analysis

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).

Urine (no later than 14 days after rash onset).
Case Classification

Confirmed: a case that is laboratory confirmed or meets the clinical case definition and is

epidemiologically linked to a confirmed case

Probable: meets the clinical case definition, has no or noncontributory serologic or virologic testing,

and is not epidemiologically linked to a confirmed case

Suspected: any generalized rash illness of acute onset

Clinical Features
Subclinical Infection

Thirty to 50% of rubella infections are asymptomatic.

Incubation Period

The incubation period varies from 14-23 days, but usually 16-18 days.

Prodrome

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.

Rash

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.
Rubella Immunity
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 Investigation
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:

 contact with a person who is suspected of having rubella disease

 travel or gathering

 medical facility

 list all contacts and determine those who do not have rubella immunity (pregnant women, household, school, work, physician/ER, clubs, carpool and other contacts)

2. Upon confirmation of the clinical diagnosis as suspected rubella,

 collect acute and convalescent sera for serological testing, send to Arizona State Laboratory and

 collect urine and nasopharyngeal swab for viral isolation, send to Arizona State Laboratory

3. Notify ADHS as soon as possible by calling [phone]

4. Vaccinate all susceptible contacts

5. Monitor all susceptible contacts (contacts who do not have evidence of rubella immunity) for symptoms suggestive of rubella infection for 23 days after last exposure.

6. Pregnant women with known or suspected rubella infection on exposure should be promptly referred to their prenatal care provider with this information (VERY IMPORTANT).

The following time line depicts the clinical course of rubella and may be useful in an investigation:

Exposure and Incubation Period (12-23 days)			Rash (~3 days)	Communicability
weeks: -3	-2	-1	Rash Onset	1	2
Onset of rash minus 18 days is probable exposure DATE:	Onset of rash minus 7 days is probable start of infectious period DATE:	PRODROME: Mild symptoms include low-grade fever, malaise, swollen glands, and URI symptoms	DATE:	Onset of rash plus 7 days is probable end of infectious period DATE:
			Arthralgia may occur at same time or shortly after rash

Rubella Outbreak Control Strategies

1. 
   Following laboratory confirmation of rubella in setting, consider declaring outbreak and initiating a press release.
   
2. 
   Alert contacts (including parents of contacts) to situation (see “Sample Rubella Alert Letter”)
   
3. 
   If outbreak is in school or daycare, exclude unimmunized children/staff until outbreak has been declared over.
   
4. 
   Provide vaccination to umimmunized contacts.
   
5. 
   Notify physicians in community of outbreak.
   
6. 
   End of outbreak should be declared when two incubation periods have passed since the onset of the last case.
   

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