Mumps is a highly contagious viral infection that is transmitted via airborne droplets. The incidence is now very low in the US because of the combined measles, mumps, and rubella (MMR) vaccine. The condition primarily affects children between the ages of five and fourteen. Classically, it manifests with parotitis, which initially occurs unilaterally, but typically progresses to involve both sides. The lateral cheek and jaw area usually show marked swelling and the ears may protrude. Other symptoms include low-grade fever, malaise, headache, and possible swelling of other salivary glands. The diagnosis of mumps is largely based on clinical findings. Many cases, however, present with nonspecific features and are not easily recognizable as mumps. If possible, diagnosis should be confirmed with laboratory tests. Treatment is symptomatic. Rare complications include orchitis, aseptic meningitis, hearing loss, and pancreatitis. Immunization offers the best protection against future exposure. Mumps is a self-limiting disease, followed by lifelong immunity. The prognosis in uncomplicated cases is very good.
- Incidence: drastically declined in the US since the introduction of the MMR vaccine 
- Peak age: 5–14 years of age
- Sex: ♂ = ♀ for parotitis; (however, males are three times more likely to have CNS complications) 
Epidemiological data refers to the US, unless otherwise specified.
- Pathogen: Mumps virus from the Paramyxoviridae family
- Humans are the sole host and the virus is transmitted via airborne droplets.
- Direct contact with contaminated saliva or respiratory secretions
- Contaminated fomites
- Highly infectious
- Affected individuals are contagious ∼ 3 days before and up to 9 days after disease onset (when the parotid gland becomes swollen).
Asymptomatic cases are also contagious.
- Incubation period: 16–18 days 
Classic course: inflammation of the salivary glands, particularly parotitis 
- Duration of parotitis: at least 2 days (may persist > 10 days)
- Chronic courses are rare.
Subclinical presentation 
- Nonspecific or predominantly respiratory symptoms
- Asymptomatic (in 15–20% of cases) 
Laboratory tests, if available, should be conducted to confirm the suspected cases (especially if presentation is atypical or there is a mumps outbreak). 
Differential diagnosis of parotid swelling 
|Features||Mumps||sialosis) (||salivary stones) (|
|Parotid swelling|| || || || || |
|Pain|| || || || || |
|Fever|| || || || || |
|Other findings|| || || || |
- Differential diagnosis of orchitis: epididymitis,
- Differential diagnosis of aseptic meningitis (See “ .”)
The differential diagnoses listed here are not exhaustive.
Mumps is usually self-limited with a good prognosis (unless complications arise). Treatment is mainly supportive care.
- Definition: inflammation of the testis
- Epidemiology: most common complication of mumps in postpubertal male individuals (20–30% in unvaccinated postpubertal and 6–7% in vaccinated males) 
- Clinical features
- Complications: : may lead to atrophy and, in rare cases, hypofertility
Other complications 
- Aseptic (1–10% of cases); : predominantly mild course and usually no permanent sequelae
- Encephalitis (< 1% of cases)
- Acute pancreatitis (< 1% of cases)
- Hearing loss (extremely rare)
We list the most important complications. The selection is not exhaustive.
- General measurements 
- Primary immunization: a live attenuated vaccine in combination with measles and rubella vaccine (i.e., MMR) and, if necessary, varicella (MMRV)