Mumps is an acute (sudden) viral illness.
The virus that causes mumps is a paramyxovirus. It is spread by direct contact as well as by airborne droplets and saliva.
Mumps was once considered one of the inevitable infectious diseases of childhood. Since a mumps vaccine became available in 1967, the incidence of mumps has declined in the U.S., but there are still many underimmunized populations (for example, more blacks than whites have not yet been immunized).
Mumps usually presents with inflammation of the salivary glands, particularly the parotid glands (salivary glands near the ears). A child with mumps often looks like a chipmunk with a full mouth due to the swelling of the parotids. (Mumps is also called epidemic parotitis).
Mumps can cause inflammation of tissues other than the salivary glands. Most frequently, the covering and substance of the central nervous system are inflamed causing meningoencephalitis. The pancreas is another target organ resulting in pancreatitis.
Especially after adolescence, mumps tends to affect the ovary (oophoritis) and the testis (orchitis). The mature testis is particularly susceptible to damage from mumps, which can lead to infertility.