Rubella Flashcards
What family of virus is this deck about?
Togaviridae
What two viruses are included in the Togaviridae family
- Rubella(German Measles)
2. Alphavirus
Genome of Rubella
- positive
- single stranded
- RNA
- 1segment
Capsid shape of Rubella
Icosahedral
Is it enveloped?
Yes
Inactivated by what?
- chemical agents
- UV
- Low pH
- heat
Replication process for Rubella
-positive RNA so immediately binds to ribosome
How is the mRNA of rubella translated
- 2/3 genome is translated into one polypeptide protein
- polypeptide protein cleaved into 4
- protease and RNA dependent RNA polymerase
- 1/3 genome into capsid, envelope
Risk to pregnant woman
- pregnant women: fetal death or congenital defects
- congenital rubella syndrome
Transmission of Rubella
-person to person via droplets from respiratory tract
Incubation period of Rubella
14 to 21 days
Symptoms of Rubella in children
- rash, low fever, mild conjunctivitis
- rash on face, neck then body for 1-3 days
- swollen lymph nodes behind ears and in neck
Additional symptoms of Rubella typically in adults
- arthritis
- painful joints
- 3 to 10 days
Description of congenital rubella syndrome
- hearing impairments
- eye and heart defects
- autism, diabetes mellitus, thyroid dysfunction
Most common complications from congenital rubella syndrome
- hearing loss
- congenital heart disease including PDA
- ocular abnormalities ie cataracts
- Microencephaly
Reservoir of rubella
Only humans
Location of infection by the rubella virus
- nasopharynx and lungs
followed by - lymph nodes and monocyte macrophage system
Antibodies can prevent which symptoms of rubella
- primary viremia
- secondary viremia
- transmission to fetus
Epidemiology of Rubella
- eliminated within the United States
- endemic in parts of the world
Diagnosis of Rubella
- titres of antibody IgG
- rebulla specific IgM + rash confirms diagnosis =
Control for Rubella
- MMR vaccine(measles, mumps, rubella)
- MMRV vaccine(adds varicella)
Does Rubella have viremia
Yes
