Rubella (German Measles)

Reportable by Laboratories and Providers

About this Reportable Disease

Infectious agent:  Rubella virus

Description of illness: Rubella is a brief, vaccine-preventable viral illness characterized by a mild maculopapular rash that is rare in the United States but can be introduced by ill travelers. The rubella rash occurs in 50%-80% of rubella-infected persons and is sometimes misdiagnosed as measles or scarlet fever. Children usually develop few or no symptoms, but adults may experience a 1-5 day prodrome of low-grade fever, headache, malaise, mild coryza, and conjunctivitis.  Arthritis occurs in up to 70% of infected women, but is rare in men or children. Rubella is a contagious illness transmitted through direct or droplet contact from nasopharyngeal secretions with an incubation period of 17 days (range: 12-23 days). A person is most infectious when rash is erupting, but can shed the virus from 7 days before to 7 days after rash onset.  The most serious complication from rubella is the harm an infection can cause an unvaccinated pregnant woman’s developing baby, complications includes: miscarriage; stillbirths; and severe birth defects, known as congenital rubella syndrome (CRS).

Interactive Disease Data


Laboratory Reporting for this Disease

Reporting requirements apply to all laboratories located within Tennessee, as well as laboratories outside of Tennessee that test residents of Tennessee, including laboratories located within healthcare facilities. Healthcare providers and laboratories in the same healthcare facility both have a duty to report. The type of organisms and analytes laboratories must report to TDH for 2026 are indicated, and there are several ways laboratories can report results to TDH.

Information about this Reportable Disease for Healthcare Providers

Clinical Summary

  • Rubella is a contagious viral illness caused by the rubella virus and is spread primarily via respiratory droplets. 
  • The illness is often mild or even asymptomatic (about 25-50% of infections show no noticeable symptoms). 
  • Typical signs include a low-grade fever, swollen lymph nodes (often posterior auricular/sub-occipital), and a pink maculopapular rash that begins on the face and spreads to the body within ~24 hrs, lasting around 3 days. 
  • No specific antiviral treatment exists; management is supportive (rest, symptom relief) and isolation to prevent spread, especially important if a pregnant woman might have been exposed.
  • The greatest risk is when rubella infects a pregnant person (especially early in pregnancy) — this can lead to miscarriage, stillbirth, or the dreaded Congenital Rubella Syndrome (CRS) with heart, eye, hearing, and other defects. 

Healthcare Provider Reporting

Healthcare reporting requirements apply to all providers located within Tennessee, as well as providers whose patients reside in Tennessee.

Providers must report cases of all diseases and conditions listed through one of these methods:

• Mail or fax a completed PH-1600 form to your local health department or fax to the state health office at (615) 741-3857

• Send automatically via electronic case reporting (eCR). See this TDH webpage for more information on eCR, register at the Trader Partner Registration website, or contact MU.Health@tn.gov for assistance.

• Submit online via NBS. NBS is TDH's reportable disease system. To request an NBS account for reporting Complete this user survey to request an NBS account for reporting. 

• Blood lead levels can be sent via fax ( (615) 741-3857), entered online, or reported using the instructions at this link. 

Information about this Reportable Disease for the Public

What It Is

Rubella is an infection caused by the rubella virus (a positive-stranded RNA virus of the Matonaviridae family).

It spreads from person to person through direct contact or droplets from nasopharyngeal secretions.

The incubation period averages 17 days (range ~12-23 days), and infected persons are most contagious around the time the rash appears. 

Types

There are basically two clinical “types” or presentations:

Symptomatic rubella, where the characteristic rash and symptoms appear.

Subclinical (inapparent) infection, where people are infected but show little or no signs. The fact that up to ~25-50 % of infections may be asymptomatic makes rubella tricky to diagnose just by looking. 

Signs and Symptoms

When symptomatic, rubella commonly features:

A mild maculopapular rash, which usually begins on the face, then becomes generalized within ~24 hours, lasts around 3 days. Occurs in about 50-80 % of infected persons.

Lymphadenopathy (swollen lymph nodes) often in posterior auricular or suboccipital nodes, sometimes generalized; may precede the rash and last ~5-8 days.

Mild fever and sometimes upper‐respiratory symptoms; arthralgia/arthritis may occur, especially in adult women (up to ~70 % in adult women). 

Treatment

There is no specific antiviral therapy for rubella. 

Management is largely supportive: isolate infected persons (e.g., 7 days after rash onset) to prevent spread. 

In outbreak settings (especially where pregnant women might be exposed), prompt public-health measures, vaccination of susceptible contacts, and exclusion of non-immune people in high-risk settings are recommended.

This Page Last Updated: March 25, 2026 at 8:53 PM