Rubella Virus (German measles)

 Rubella Virus (German measles)

Rubella virus is an RNA enveloped virus.

It cause Germen measles or rubella disease in human beings.

This virus infect commonly seen during pregnancy thsy may be acquired congenitally or postnatally.

Structure

Rubella virus has single stranded positive RNA virus.

This virus is enveloped.

Envelope spikes of glycoprotein are present at surface.

Spherical, 50-70nm in diameter.

Sources and Mode of Transmission

Infected fetus major source of infection during miscarriage.

Transmitted by inhalation and also by blood stream.

Pathogenesis

Virus acquired by inhalation.

Multiplies at site of entry a d enter in blood stream to skin.

Major harm is only to fetus via blood stream.

It may acquire; 

Congenital rubella

(Rubella virus cross placental barrier, cause cardia defect, deafness etc).

Postnatal rubella

(Acquired by inhalation)

After incubation period 2-3 week viraemia occurs.

Symptoms

Fever

Muscular pain

Myocarditis

Bone lesions

Laboratory Diagnosis

Specimen collection; blood or throat swab

Animal and tissue culture

ELISA (serological test)

Used for detecting viral antibodies IgM and IgG antibodies.

If only IgM present, it shows acute infection.

If only IgG present shows past infection or vaccine induced immunity.

Prophylaxis and Treatment

Protection is acquired by immunization, combined measles -mumps- rubella (MMR) vaccine is recommended for all infant.

Rubella only infect fetus, so rubella prophylaxis is very important for woman of child bearing age.