Rubella at a Glance
Rubella (German measles) is a usually mild viral exanthem caused by rubella virus. Many cases are subclinical. The key public‑health concern is infection during early pregnancy, which can cause congenital rubella syndrome (CRS).
Contents
Incubation and Infectious Period
- Incubation: typically 14–21 days (about 18 days).
- Infectious: from ~7 days before to 7 days after rash onset. Infants with CRS can shed virus for months and require special precautions.
Typical Symptoms and Course
- Low‑grade fever, malaise, mild upper‑respiratory symptoms, and conjunctivitis.
- Tender postauricular, posterior cervical, and occipital lymphadenopathy is characteristic.
- Rash: fine, pink maculopapular eruption starting on the face and spreading caudally; often resolves within 2–3 days without desquamation.
- Arthralgia/arthritis is common in adolescents and adults, especially females (hands, wrists, knees).
Transmission
- Person‑to‑person via respiratory droplets and short‑range aerosols; transplacental transmission to the fetus during maternal infection.
- Humans are the only reservoir; outbreaks occur in undervaccinated communities.
Complications (Uncommon in Immunocompetent Hosts)
- Thrombocytopenic purpura; encephalitis/meningoencephalitis (rare); myocarditis (rare).
- In pregnancy: miscarriage, stillbirth, or CRS.
Congenital Rubella Syndrome (CRS)
- Highest fetal risk with maternal infection in the first trimester.
- Classic findings: sensorineural deafness, congenital heart disease (e.g., PDA, peripheral pulmonary artery stenosis), and ocular defects (cataracts, retinopathy). Other features: microcephaly, developmental delay, hepatosplenomegaly, “blueberry muffin” rash.
- Infants with CRS may shed virus for prolonged periods; implement infection‑control precautions and coordinate with public health.
Diagnosis
- NAAT (PCR) from respiratory specimens or serology (rubella‑specific IgM; paired IgG seroconversion) supports diagnosis. Serology can be confounded by vaccination; use appropriate testing algorithms.
- For pregnancy exposures: check rubella IgG immunity promptly; consult obstetrics and public health for follow‑up and fetal assessment.
Prevention — Vaccination
- MMR (measles‑mumps‑rubella) provides reliable protection. Usual schedule: first dose at 12–15 months; second at 4–6 years; catch‑up for unvaccinated children and adults per local guidance.
- Ensure documented immunity in healthcare workers, students, and travelers.
- Contraindicated in pregnancy and severe immunodeficiency. Vaccinate non‑immune persons postpartum; avoid pregnancy for a period after vaccination per guidance.
After Exposure (PEP Considerations)
- Routine post‑exposure immunoglobulin is not reliable for preventing rubella or CRS. It may be considered in limited circumstances (e.g., non‑immune pregnant person with exposure who elects to continue pregnancy) to potentially modify disease; requires specialist/public‑health consultation.
- MMR vaccine is not used as PEP for pregnant individuals and is contraindicated during pregnancy.
Isolation and Reporting
- Isolate suspected/confirmed cases until 7 days after rash onset; use droplet precautions. CRS infants require extended precautions.
- Rubella is a notifiable disease in many regions — report promptly to enable contact tracing and outbreak control.
Key Takeaways
- Rubella is often mild but can be devastating in early pregnancy; vaccination prevents disease and CRS.
- Recognize the characteristic lymphadenopathy and rapid, short‑lived rash.
- Manage exposures in pregnancy with urgent serologic evaluation and specialist input.
Educational information only; follow local public health guidance and consult clinicians for individual care.
