Questions & Answers

What causes mumps?
Mumps is caused by a virus.

How does mumps spread?
Mumps spreads from person to person via droplets of saliva or mucus from the mouth, nose, or throat of an infected person, usually when the person coughs, sneezes, or talks. The virus may also be spread indirectly when someone with mumps touches items or surfaces without washing their hands and then someone else touches the same surface and rubs their mouth or nose. Mumps is less contagious than measles or chickenpox.

How long does it take to show signs of mumps after being exposed?
The incubation period of mumps is usually 16–18 days, but can range from 12–25 days.

What are the symptoms of mumps?
Individuals with mumps usually first feel sick with nonspecific symptoms like headache, loss of appetite, and low-grade fever.

The most well-known sign of mumps is "parotitis," the swelling of the salivary glands, or parotid glands, below the ear. Parotitis occurs only in 30%–40% of individuals infected with mumps. Some people with mumps have no signs or symptoms of illness; others may have respiratory symptoms or only nonspecific symptoms such as headache, loss of appetite, and low-grade fever.

How serious is mumps?
In children, mumps is usually a mild disease. Adults may have more serious disease and more complications.

What are possible complications from mumps?
Central nervous system involvement (meningitis) is common, but is usually not serious. Meningitis (with headache, stiff neck) occurs in up to 15% of people with mumps, but usually resolves without any permanent damage. Up to 50% of postpubertal males experience orchitis (testicular inflammation) as a complication of mumps. This may involve pain, swelling, nausea, vomiting, and fever, with tenderness of the area possibly lasting for weeks. Approximately half of patients with orchitis have some degree of testicular atrophy, but sterility is rare.

Inflammation of the ovaries (oophoritis) and/or breasts (mastitis) can occur in females who have reached puberty. An increase in spontaneous abortion (miscarriage) has been found among women who developed mumps during the first trimester of pregnancy in some studies but not in others; however, there is no evidence that mumps causes birth defects. Deafness, in one or both ears, can occur in approximately one per 20,000 reported cases of mumps.

Is there a treatment for mumps?
There is no "cure" for mumps, only supportive treatment (bed rest, fluids, and fever reduction).

How is mumps diagnosed?
Mumps is diagnosed by a combination of symptoms and physical signs and laboratory confirmation of the virus, as not all cases develop characteristic parotitis and not all cases of parotitis are caused by mumps.

How long is a person with mumps contagious?
People with mumps are usually considered most infectious from a few days before until 5 days after the onset of parotitis. Therefore, CDC recommends isolating mumps patients for 5 days after their glands begin to swell.

What should be done if someone is exposed to mumps?
If the exposed person has not been vaccinated against mumps, receiving the vaccine after exposure to the virus will not help prevent disease if the child has already been infected. However, if they did not become infected after this particular exposure, the vaccine may help protect him or her against future exposure to mumps.

How common is mumps in the United States?
Due to good immunization coverage, mumps is now rare in the United States. An estimated 212,000 cases occurred in 1964, while only 454 cases were reported in 2008. Large outbreaks of mumps occurred in the United States in 2006 and 2009—10 with more than 6,000 and 3,000 cases, respectively, reported in those years.

Can someone get mumps more than once?
People who have had mumps are usually protected for life against another mumps infection. However, second occurrences of mumps do rarely occur.
 

Questions and answers about mumps vaccine

Technical content reviewed by the Centers for Disease Control and Prevention, December 2010