Mumps is an acute viral infection caused by the mumps virus, a member of the Paramyxoviridae family. Infection is characterized by swollen salivary glands, which are along the jaw line, below the ears, and within the cheek. It is generally a mild and self-limiting disease, in that there is no treatment and it has to run its course, but complications can occur.
Mumps Virus Communicability
The virus replicates in the upper respiratory tract, spread by coughing and sneezing in proximity to other people. The incubation period is 16-18 days from exposure to onset of symptoms. The infection is contagious from 3 days prior to symptoms being visible to 9 days after the appearance of symptoms. Approximately 20% of infections are asymptomatic.
Mumps Infection
In addition to swollen parotid salivary glands (in 30-40% of all infections), the physical manifestations of mumps include fever, headache, exhaustion, and loss of appetite, and 50% of infections have respiratory symptoms. Severe complications are more common in adults than children, with the exception of deafness. Complications can include inflammation of the pancreas, testicles, ovaries and breasts, and the brain and spinal cord (encephalitis). Pregnant women who become infected with the mumps virus may experience miscarriage.
Mumps Prevention
The mumps vaccine was first licensed in the United States in 1967, but routine use and inclusion in the MMR (measles – mumps – rubella) vaccine occurred in 1989. This increased vaccination coverage resulted in steadily decreasing numbers of infections. Between 2001 and 2005, the United States had less than 300 cases reported per year. In 2006, a 4,000 case outbreak occurred in the Midwest United States following a mumps peak in the UK in 2005. Mumps is endemic to many parts of the world.
Another vaccine is MMRV (MMR plus varicella) or a monovalent version of the vaccine. There was some controversy in recent years about the MMR vaccine due to speculation on an association between autism and the mercury-based preservative thimerosal. The preservative was developed in the 1930s, but it has not been in the vaccines since 2001, and the Merck version of the vaccine (MMRII) has never contained the preservative.
The first vaccine dose is given between 12 and 15 months age, and the booster can be given 4 weeks later or before the start of Kindergarten at 4-6 years of age. Some immunocompromised children may not be able to receive the vaccine, they should be protected from disease if approximately 90% of their peers are vaccinated (called herd immunity). The first dose of the vaccine is 78%-91% effective at establishing immunity.
MMR Vaccine Side Effects
Less than one-fourth of those who are vaccinated with MMR will be susceptible to side effects, including a fever and rash one to two weeks after receiving the injection. One per one million vaccinations will result in an allergic reaction. The more common side effect is lymph node swelling, a side effect of the immune response. Low platelet counts occur in 1 of every 100,000 vaccinations in the United States. Neurological side effects are considered coincidental but should be treated to determine the cause.
For information on the other diseases prevented with the MMR vaccine, read about Rubella and Measles.
 |
