Infection: Mumps

Question 1

What causes mumps?

Answer 1

Paramyxovirus

RNA virus

Question 2

How is paramyxovirus transmitted?

Answer 2

Respiratory droplets or direct contact

Infectious periods around parotid inflammation - 7 days before and after

Question 3

Does infection result in life long immunity?

Answer 3

Yes

Question 4

Why has the incidence declined?

Answer 4

MMR vaccine

Decrease in uptake of vaccine in 1990s - rise in unimmunised children and young adults

Question 5

The virus replicates in respiratory tract epithelial cells then gains access to parotid glands before…

Answer 5

Further dissemination to other tissues

Question 6

What clinical features occur?

Answer 6

Fever, malaise, myalgia, parotitis - only one side of face may be swollen initially, bilaterally involvement may occur

Parotitis - may cause earache, pain on eating and drinking

Question 7

What complications can occur?

Answer 7

Pancreatitis - generally mild 
Frequent nervous system involvement - sensorineural deafness (usually unilateral and transient) , viral meningitis and encephalitis 
Orchitis 
Oophritis 
Arthritis 
Nephritis

Question 8

Lymphocytes are seen in the CSF in what percentage of cases?

Answer 8

50% - meningeal signs are only seen in 10%

Question 9

How common is encephalitis?

Answer 9

1 in 5000

Question 10

Is orchitis common?

Answer 10

No uncommon in prepubertal males

Question 11

Is infertility due to orchitis common?

Answer 11

Very rare

Some evidence of reduced sperm count

Question 12

What is often elevated due to parotitis?

Answer 12

Plasma amylase levels