Outline
A. Overview
B. Pathology
C. Clinical Manifestation
D. Diagnosis
E. Treatment
F. Prevention
A. OVERVIEW
Member of Togaviridae family and the only member of the genus Rubivirus
Single strand RNA , enveloped
Only 1 antigenic type
Humans are its only known reservoir
B. PATHOLOGY
Transmission: respiratory droplets
Primary implantation and replication: at nasopharynx, the spread to the
lymph nodes.
In subsequent viremia, there is placental infection in pregnant women and
placental viral replication leads to infection of fetal organs.
Hallmark of Fetal infection: chronicity, with persistence throughout fetal
development in utero and for up to 1 year after birth.
Shedding of virus: 7 days before rash to 5-7 days after
C. CLINICAL MANIFESTATION
Acquired Rubella
Commonly presents with maculopapular rash that lasts up to 3 days
Rash is mild and hard to detect in dark skin
In children: rash is usually the first sign of illness
In older children and adults: 1 to 5-day prodrome precedes rash (includes
low-grade fever, malaise, upper respiratory symptoms
Incubation period 14 days (12-23 days)
Lymphadenopathy (occipital and post-auricular): noted during second
week after exposure
Common in infected adults, particularly women
Arthralgia
Arthritis
Less common complications
Thrombocytopenia
Encephalitis
, Figure 1. Maculopapular rash
Congenital Rubella Syndrome
Most serious consequence of rubella Infection, develop when a pregnant
woman becomes infected during 1st Trimester
Complications:
Miscarriage or Fetal death
Premature delivery
Live births with congenital defects
CRS: term used for constellation of birth defects due to rubella virus
infection of infant in utero
Myriad of physical defects commonly to eyes, ears, and heart
Transient physical manifestations: thrombocytopenia with purpura or
petechiae (eg. dermal erythropoiesis, "blueberry muffin syndrome)
"Infants with congenital rubella infection only:” refers to infants born
with congenital rubella virus infection but have no apparent signs and
symptoms of CRS