Mumps, a notifiable disease in many countries, is a condition caused by a contagious paramyxovirus and occurs predominantly in the pediatric population. It is easily spread from one person to another via the respiratory route and has an incubation period between 12 – 25 days. Persons are not contagious early in the incubation period, but are infectious right before the classical symptoms appear, and remain communicable for at least a few more days after becoming symptomatic.
Infected persons classically experience parotitis, which is the painful swelling and inflammation of the parotid salivary glands. As many as 3 of every 10 unvaccinated patients may not have any symptoms. It is usually considered a mild disease. However, disease-associated serious complications may occur in a few individuals, and include inflammation of the testicles, ovaries, breast, and pancreas. Patients may also have loss of hearing as well as aseptic meningitis and, though rare, encephalitis.
Treatment and Prognosis
To date there is no specific antiviral or other drug therapy for mumps. Hence patients must allow the disease to run its course. Therapy is mainly focused on treating the symptoms and preventing complications. Symptomatic treatment includes applying ice or heat to reduce the pain and discomfort of swollen parotid glands, as well as the use of non-aspirin containing drugs, such as ibuprofen or acetaminophen, to modulate pain and fever. (NB: children under the age of 12 should not be given aspirin). Patients are also encouraged to increase their fluid intake.
Children with mumps must be kept away from having contact with other children at daycare centers or school. Affected individuals should isolate themselves from others, such as at their workplace or grocery store, for at least 5 days after the onset of parotitis. All materials that may have been soiled with bodily secretions, such as tissues and towels, should be appropriately disposed of.
Patients who are symptomatically treated usually recover well. Sterility and deafness due to mumps are serious but rare disease consequences. Most patients who develop complications like meningoencephalitis usually have a favorable outlook. However, there may be neurological damage in a few cases and some may unfortunately have fatal outcomes.
First licensed in 1967, the measles, mumps and rubella (MMR) vaccine is the key to preventing mumps in the first instance. Nearly all people who have had the standard two-dose MMR vaccine will be protected from the virus if the vaccine was given before infection. Between 12 – 15 months old, children should receive their first dose of MMR vaccine. A second dose is given to children later, but the precise timing varies among countries.
If at least 90% of the population is vaccinated against the mumps virus, then a phenomenon known as ‘herd immunity’ sets in, preventing infection of those who are not vaccinated. This gives unvaccinated persons a false sense of security, whereas the truth is that they remain unaffected due to the absence of unvaccinated and therefore susceptible contacts nearby to infect them. However, failure to acquire adequate vaccination against the condition may result in an epidemiological shift of the disease from the pediatric population to older groups with the potential to cause more deleterious effects.
Many meticulously conducted studies have not found any links to the popular belief that the vaccine causes autism. Moreover, allergic reactions to the MMR vaccine are very rare. Parents who choose not to vaccinate their children should understand that this option reduces the protective effect of herd immunity, and increases the risk of their children contracting the condition. This is unfortunate, because the MMR vaccine is very effective, safe and provides immunity that is long-lasting.
Reviewed by Liji Thomas, MD