Mumps

Key Features

Essentials of Diagnosis

• Exposure 12–25 days before onset

• Painful, swollen salivary glands, usually parotid

• Frequent involvement of testes, pancreas, and meninges in unvaccinated individuals

• Mumps can occur in appropriately vaccinated persons in highly vaccinated communities

General Considerations

• Children are most commonly affected; however, in outbreaks, infection can affect patients in their second or third decades of life

• Mumps is more serious in adults than in children and appears to occur more commonly in males

• Incubation period is 12–25 days (average, 16–18 days)

• Transmission

  • Direct contact with respiratory secretions or saliva or infected surfaces

  • Can also be airborne or via droplets

  • Can spread rapidly in congregate settings, such as colleges and schools

  • Up to one-third of affected individuals have subclinical infection, which is still transmissible

Demographics

• From January 2016 to June 2017, 9200 cases were reported, including a large outbreak of close to 3000 cases in one Arkansas community

• Between January 1 and September 13, 2019, 47 states and the District of Columbia in the United States reported 2363 mumps cases

Clinical Findings

Symptoms and Signs

• Fever and malaise are variable but often minimal in young children

• Parotid tenderness and overlying facial edema

  • Most common physical findings

  • Typically develop within 48 hours of the prodromal symptoms

  • Usually, one parotid gland enlarges before the other, but unilateral parotitis occurs in 25% of patients

  • The parotid duct (orifice of Stensen) may be red and swollen

• Trismus may result from parotitis

• Involvement of other salivary glands (submaxillary and sublingual) occurs in 10% of cases

• Orchitis

  • Testes most common extra salivary disease site in adults

  • High fever, testicular swelling, and tenderness (unilateral in 75% of cases)

  • Usually develops 7–10 days after the onset of parotitis

Differential Diagnosis

• Swelling of the parotid gland may be due to

  • Calculi in the parotid ducts

  • Tumors

  • Cysts

• Parotitis may be produced by pyogenic organisms

  • Staphylococcus aureus

  • Gram-negative organisms

  • Drug reaction (phenothiazines, propylthiouracil)

  • Other viruses (HIV, influenza A, parainfluenza, EBV infection, coxsackieviruses, adenoviruses, HHV-6)

• Sarcoidosis

• Cirrhosis

• Diabetes

• Bulimia

• Pilocarpine usage

• Sjögren syndrome

Diagnosis

• An elevated mumps-specific serum IgM is considered diagnostic

• Repeat testing 2–3 weeks after the onset of symptoms is recommended if the first assay is negative because the rise in IgM may be delayed

• Nucleic acid amplification techniques, such as real-time PCR, are more sensitive than viral cultures

• A fourfold rise in complement-fixing antibodies to mumps virus in paired serum IgG also confirms infection

• Anti-mumps IgM and IgG in the CSF can confirm the diagnosis of mumps-associated meningitis

• The virus can also be isolated from CSF early in aseptic meningitis

• Mild leukopenia with relative ...