Mumps (Epidemic Parotitis)

Acute, frequently mild viral infection characterised in the majority of affected individuals by painful enlargement of the parotid and or other salivary glands but occasionally associated with viraemic complications

• Mumps virus-RNA virus
• Genus paramyxovirus of the paramyxoviridae family
• Same group with RSV, PIV, New Castle, LCM

• Worldwide distribution but endemic in most unvaccinated communities
• Reservoir of infection is human
• Spread –
• Airborne droplets
• Direct contact
• Body fluid contaminated fomites, esp with saliva or urine.
• Male:Female ratio distribution almost equal
• Age incidence: Peak 5-9 yrs, with over 80% seen in under 15; Also seen in young adults, colleges and & work institutions
• Outbreaks related to lack of immunization

• Entry via pharynx, oro- or nasopharnx
• Primary viral replication in the respiratory tract epithelium
• Viraemic dissemination to several organs/glands, but chiefly the salivary and other exocrine glands like the pancreas, gonads, thyroid, hearing organs, CNS
• Edema is out of tune with the extent of glandular involvement with consequent evidence of a more visible than palpable enlargement
• Concomitant ductal pathology

• Causative virus can be identified from the saliva some 1 wk before swelling and 8-9 days after
• Peak transmission / viral shedding , 1 day before and not more than 3 days after the swelling would have regressed
• Urinary isolation, from the day the swelling is noticed up to 2 weeks after

• Chiefly a parotid or less commonly other salivary gland affair
• Fills space anterior to the mastoid & posterior to the mandibular (erasure oedema)
• Swelling progresses downward and forward in a series of crescents limited above by the zygoma but along an axis extending antero-inferiorly from the tragus to the mid madibular ramus.
• Swelling may cause upward and outward displacement of the pinna.
• Swelling painful esp. on tasting sour stuff, and also tender to touch
• Evidence of other salivary gland affectation(10-15%),swelling @ the angle of the jaw, floor of the mouth /submentum
• Concomitant swelling & redness of the duct & opening

Non-Salivary Manifestations

• Fever, usually low grade
• Oedema of the homolateral pharynx with soft palate & tonsillar displacement +/- laryngeal extension/oedema
• Sternomanubrial edema
• Upper abdominal pain (pancreatitis) - Pancreas involved in some 75% of cases.
• Features of viraemic complications - encephalitis may occur with or without parotitis.

Of Viraemic origin:

• Pancreatitis.
• Meningoencephalitis – note propensity for high CSF pleocytosis- up to 500 – 2000 cells , usually lymphocytes
• Sensorineural deafness
• Oophoritis/orchitis +/- epididimitis
• Myocarditis.
• Thyroiditis
• Arthritis

1. Clinical
2. Microbiologic:
1. Virus culture from saliva CSF, urine, blood, brain .
2. Culture in human or monkey kidneys; Identification is by haemadsorption – occassional cytopathic effect
3. EIA for mumps IgG & IgM, frequently detectible after the 1st few days of swelling – Initial detectn of IgM diagnostic and may remain high for months (ref anti V vs anti F)
4. 4-fold rise of IgG diagnostic but Cross reactivity with PIV well recognised.
3. Non-Micro: Elevated serum amylase in 75%
4. Nonspecific:
• Leukopaenia with relative lymphocytosis
• Mumps skin test- unreliable

• Non-specific treatment including avoidance/dietary modification, analgesics, bed rest, testicular support, NSAID for arthritis & Mx of encephalitis etc
• Mumps is preventable with live attenuated virus derived from Jeryl Lynn strain of the mumps virus prepared from Chick or hen embryo.
• Given as MMR in childhood with 4-6 wks btw initial and booster – usually initially @ 4-6 yrs but in any case b4 11-12yrs
• Avoid in pregnancy, acute febrile states, anaphylaxis/allergy to vaccine component to and immuno-compromised
• Maternal A/B protective, 1st 6 months of life.