Mumps (epidemic parotitis) is a contagious viral infection that causes painful enlargement of the salivary glands. The infection may also affect the testes, brain, and pancreas, especially in adults.
Children become infected with mumps by breathing in small airborne droplets of moisture coughed out by an infected person or by having direct contact with objects contaminated by infected saliva. Mumps is less contagious than measles or chickenpox. In heavily populated areas, it occurs year-round but is most frequent in late winter and early spring. Epidemics may occur when people without immunity are crowded together. Although the infection may occur at any age, most cases occur in children 5 to 10 years old. The infection is unusual in children younger than 2 years. One infection with the mumps virus usually provides lifelong immunity.
Symptoms and Diagnosis
Symptoms begin 14 to 24 days after infection. Most children develop chills, headache, poor appetite, a general feeling of illness (malaise), and a low to moderate fever. These symptoms are followed in 12 to 24 hours by swelling of the salivary glands, which is most prominent on the second day and lasts 5 to 7 days. Some children simply have swelling of the salivary glands without the other symptoms. The swelling results in pain when chewing or swallowing, particularly when swallowing acidic liquids, such as citrus fruit juices. The glands are tender when touched. At this stage, the temperature usually rises to 103 or 104° F (about 39.4 or 40° C) and lasts 1 to 3 days.
About 20% of men who become infected after puberty develop inflammation of one or both testes (orchitis). Inflammation of the testes causes severe pain. Once healed, the affected testis may be smaller, but testosterone production and fertility are usually unaffected.
Mumps leads to inflammation of the layers of tissue covering the brain (meningitis) in 1 to 10% of people. Meningitis causes headache, vomiting, and a stiff neck. Mumps also causes inflammation of the brain (encephalitis) in 1 out of 1,000 to 5,000 people. Encephalitis causes drowsiness, coma, or seizures. Most people recover completely, but some have permanent nerve or brain damage, such as nerve deafness or paralysis of the facial muscles, usually affecting only one side of the body.
Inflammation of the pancreas (pancreatitis) may occur toward the end of the first week of infection. This disorder causes abdominal pain, nausea, and vomiting, which varies from mild to severe. These symptoms disappear in about a week, and the person recovers completely.
Doctors diagnose mumps based on the typical symptoms, particularly when they occur during an outbreak of mumps. Laboratory tests can identify the mumps virus and its antibodies, but such tests are rarely needed to make the diagnosis.
Almost all children with mumps recover fully without problems, but in rare cases symptoms may worsen again after about 2 weeks.
Because vaccination against mumps is routine in childhood, beginning at 12 to 15 months of age (see Vaccinating Infants and Children), fewer than 300 cases usually occur each year. However, a 2006 mumps outbreak in the midwestern United States caused more than 2,500 cases in 4 months. Young adults had the highest infection rates, which highlighted the need for continued use of vaccination.
Once the infection has started, it just has to run its course. To minimize discomfort, children should avoid foods that require much chewing or are acidic. Analgesics, such as acetaminophen and ibuprofen, may be used for headache and discomfort. Boys or men with inflammation of the testes need bed rest. The scrotum may be supported with an athletic supporter or by an adhesive-tape bridge connected between the thighs. Ice packs may be applied to relieve pain.
If pancreatitis causes severe nausea and vomiting, fluids may be given by vein (intravenously), and intake by mouth should be avoided for a few days. Children with meningitis or encephalitis may need intravenous fluids and acetaminophen or ibuprofen for a fever or headache. If seizures develop, anticonvulsant drugs may be needed.
Last full review/revision May 2007 by Mary T. Caserta, MD