Rubella

Question 1

What is rubella

Answer 1

RNA virus in the Togaviridae family
Transmission: direct contact or droplet spread from nasopharyngeal secretions
The virus then replicates in the respiratory mucosa and local lymph nodes, which is then spread haematologically to the rest of the body
Following exposure to the virus, susceptible people will develop disease 12-23 days later
Most infectious when the rash is erupting

Question 2

What are the risk factors for rubella

Answer 2

Incomplete immunisation with no evidence of previous infection
History of exposure to contacts with rubella
Travel to an area endemic for rubella e.g. Africa, South-East Asia

Question 3

What are the symptoms of rubella

Answer 3

No specific clinical features
Asymptomatic in 50% of people

Rash (50-80%)
- Starts on the face and neck before spreading down the body and becoming generalised
- Pink/light red in colour
- Maculopapular
- Transient, usually present for 3-5 present
Lumps on the neck (lymphadenopathy)
Pain and stiffness of joints, especially fingers, wrists, and knees (arthritis or arthralgia)

Older patients may have a prodrome of fever (<39), headache, malaise, nausea, URTI, and non-purulent conjunctivitis

Question 4

What are the differentials for rubella

Answer 4

Parvovirus B19
Measles
HHV-6
Dengue fever
West Nile virus
Chikungunya virus
Zika virus
Scarlet fever

Question 5

What are the signs of rubella on exam

Answer 5

Basic obs: Low-grade fever <39
Head and neck exam: Lymphadenopathy: Suboccipital, postauricular, and cervical lymph nodes most often affected. Non-tender and mobile
Rash: pink/red in colour, maculopapular, starts on the face and neck
Conjunctivitis (non-purulent)
Joint exam: Signs of arthralgia or arthritis

Question 6

What investigations should be done for rubella

Answer 6

Bedside: Oral fluid sample/throat swab for viral culture and urine culture (positive)

Bloods: Rubella-specific IgM serum antibody for capture ELISA: Positive (acute)
FBC - normal, may show thrombocytopenia

Question 7

What is the management for rubella

Answer 7

1. NOTIFY LOCAL HPT
2. Re-assure: mild, self-limiting condition that resolves within a week
3. Supportive:
   - Adequate fluids
   - Paracetamol or ibuprofen (NOT aspirin)
   - Isolate for at least 5 days after initial development of rash
   - Avoid contact with pregnant women
4. Safety net: confusion, bleeding

+ follow up (over the phone sufficient)

Question 8

What are the complications of rubella

Answer 8

Rubella rarely causes complications in otherwise healthy people:
- Arthritis and arthralgia (most commonly in adult women)
- Bleeding disorders e.g. thrombocytopenia
- Encephalitis
- Myelitis, optic neuritis, peripheral neuritis, Guillain-Barre syndrome

Question 9

What is the prognosis for rubella

Answer 9

Most cases of rubella infection are mild (with transient rash and lymphadenopathy) and resolve spontaneously within a week — occasionally, joint inflammation and pain can occur (most often in adults).
Maternal infection in non-immune women during pregnancy can cause serious congenital abnormalities (CRS), lifelong disability, and foetal loss.

Question 10

What are the features of congenital rubella syndrome (CRS)

Answer 10

90% chance of virus being passed to the foetus if Rubella infection is in early pregnancy - multiple defects are most likely when infection occurs in the first 16 weeks

Eye defects e.g. cataracts
Hearing impairment
Cardiac abnormalities e.g. patent ductus arteriosus and pulmonary artery stenosis
CNS defects e.g. microencephaly, mental and psychomotor retardation, progressive panencephalitis
IUGR
Autism
Endocrine abnormalities e.g. diabetes mellitus, thyroid dysfunction