Mumps is a common childhood
infection caused by the mumps virus. The hallmark of
infection is swelling of the parotid gland.
Aseptic meningitis and
encephalitis are common complications of
mumps together with
orchitis and
oophoritis, which can arise in adult men and women, respectively; other complications include
deafness and
pancreatitis. Clinical diagnosis can be based on the classic parotid swelling; however, this feature is not present in all cases of
mumps and can also occur in various other disorders. Laboratory diagnosis is based on isolation of virus, detection of viral
nucleic acid, or serological confirmation (generally presence of
IgM mumps antibodies).
Mumps is
vaccine-preventable, and one dose of
mumps vaccine is about 80% effective against the disease. Routine vaccination has proven highly effective in reducing the incidence of
mumps, and is presently used by most developed countries; however, there have been outbreaks of disease in vaccinated populations. In 2005, a large epidemic peaked in the UK, and in 2006 the American midwest had several outbreaks. In both countries, the largest proportion of cases was in young adults. In the UK, susceptible cohorts too old to have been vaccinated and too young to have been exposed to natural
infections were the primary cause of the
mumps epidemic. In the USA, effectiveness and uptake in combination appear not to have been sufficient to obtain herd immunity for
mumps in populations such as college students.