Structure & Property

Transmission

Pathogenesis

Clinical findings

Laboratory diagnosis

Treatment

Family: paramyxovirus

Genome: single strand RNA, negative polarity

Size: 110-170nm

Helical nucleocapsid.

Lipoprotein envelope:

- haemagglutinin

- neuraminidase

- fusion protein

Single serotype

Neutralizing antibody is directed against haemagglutinin.

‘S’ antigen detected in complement fixation

Transmitted via respiratory droplets.

More common in children from 5 to 15 years, but not uncommon in young adults.

About 30% of children have a subclinical infection, which confers immunity.

Lifelong immunity occurs in person with disease.

Maternal antibody passes placenta and provides protection during first 6 months of life.

Infects upper respiratory tract.

Spreads through blood to infect:

- parotid gland

- testes

- ovaries

- pancreas

- meninges

Incubation period: 14-21 days

Prodromal phase:

- fever

- malaise

- anorexia

- tender swelling of parotid glands, either unilateral or bilateral.

Disease is typically benign and  resolves spontaneously within a week.

Adults tend to have more severe disease: orchitis and oophoritis are more common after puberty.

Complications:

- Orchitis in postpubertal males: if bilateral, result in sterility.

- oophorititis

- pancreatitis

- aseptic meningitis: muscular weakness and paralysis.

Diagnostic: 4 fold rise in antibody titer in hemagglutination inhibition or complement fixation test.

Isolation:

- saliva

- spinal fluid

- urine

- throat washings

‘V’ surface antigen: long-lasting immunity.

‘S’ nucleoprotein: acute infection

Haemagglutinates fowl erythrocytes.

Grows in amniotic cavity of chick embryo and in monkey and other tissue cultures, with haemadsorption.

Virus is shed in the urine.

Immunization with live, attenuated virus together with measles and rubella.

Vaccine is effective and long-lasting with little side effects.

Live vaccine should not be given to immunodeficient persons or pregnant women.

Immune globulin is not useful for preventing or mitigating mumps orchitis.