Mumps

Definition

Mumps is a relatively mild short-term viral infection of the salivary glands that usually occurs during childhood.

Description

Typically, mumps is characterized by a painful swelling of both cheek areas, although the person could have swelling on one side or no perceivable swelling at all. The salivary glands are also called the parotid glands; therefore, mumps is sometimes referred to as an inflammation of the parotid glands (epidemic parotitis). The word mumps comes from an old English dialect, meaning lumps or bumps within the cheeks.

Demographics

Mumps is a very contagious infection that spreads easily in such highly populated environments as daycare centers and schools. Although not as contagious as measles or chickenpox , mumps was once quite common. Prior to the release of a mumps vaccine in the United States in 1967, approximately 92 percent of all children had been exposed to mumps by the age of 15. In the pre-vaccine years, most children contracted mumps between the ages of four and seven. Mumps epidemics came in two to five year cycles. The greatest mumps epidemic was in 1941 when approximately 250 cases were reported for every 100,000 people. In 1968, the year after the live mumps vaccine was released, only 76 cases were reported for every 100,000 people. By 1985, fewer than 3,000 cases of mumps were reported throughout the entire United States, the equivalent of about one case per 100,000 people. The reason for the decline in mumps was the increased usage of the mumps vaccine. However, 1987 noted a five-fold increase in the incidence of the disease because of the reluctance of some states to adopt comprehensive school immunization laws. After that, state-enforced school entry requirements achieved student immunization rates of nearly 100 percent in kindergarten and first grade. In 1996, the Centers for Disease Control and Prevention (CDC) reported only 751 cases of mumps nationwide, that is, about one case for every 5 million people.

Causes and symptoms

The paramyxovirus that causes mumps is harbored in the saliva and is spread by sneezing, coughing, and other direct contact with another person's infected saliva. Once the person is exposed to the virus, symptoms generally occur in 14 to 24 days. Initial symptoms include chills, headache , loss of appetite, and a lack of energy. However, an infected person may not experience these initial symptoms. Swelling of the salivary glands in the face (parotitis) generally occurs within 12 to 24 hours of the above symptoms. Accompanying the swollen glands is pain on chewing or swallowing, especially with acidic beverages, such as lemonade. A fever as high as 104°F (40°C) is also common. Swelling of the glands reaches a maximum on about the second day and usually disappears by the seventh day. Once individuals have contracted mumps, they become immune to the disease, despite how mild or severe their symptoms may have been.

While the majority of cases of mumps are uncomplicated and pass without incident, some complications can occur. Complications are, however, more noticeable in adults who get the infection. In 15 percent of cases, the covering of the brain and spinal cord becomes inflamed ( meningitis ). Symptoms of meningitis usually develop within four or five days after the first signs of mumps. These symptoms include a stiff neck, headache, vomiting , and a lack of energy. Mumps meningitis is usually resolved within seven days, and damage to the brain is exceedingly rare.

The mumps infection can spread into the brain causing inflammation of the brain ( encephalitis ). Symptoms of mumps encephalitis include the inability to feel pain, seizures, and high fever. Encephalitis can occur during the parotitis stage or one to two weeks later. Recovery from mumps encephalitis is usually complete, although complications, such as seizure disorders, have been noted. Only about one person in 100 with mumps encephalitis dies from the complication.

About one-fourth of all post-pubertal males who contract mumps can develop a swelling of the scrotum (orchitis) about seven days after the parotitis stage. Symptoms include marked swelling of one or both testicles, severe pain, fever, nausea , and headache. Pain and swelling usually subside after five to seven days, although the testicles can remain tender for weeks.

Girls occasionally suffer an inflammation of the ovaries (oophoritis) as a complication of mumps, but this condition is far less painful than orchitis in boys.

Diagnosis

When mumps reaches epidemic proportions, diagnosis is relatively easy on the basis of the physical symptoms. The doctor will take the child's temperature, gently palpate (touch) the skin over the parotid glands, and look inside the child's mouth. If the child has mumps, the openings to the ducts inside the mouth will be slightly inflamed and have a "pouty" appearance. With so many people vaccinated as of the early 2000s, a case of mumps must be properly diagnosed in the event the salivary glands are swollen for reasons other than viral infection. For example, in persons with poor oral hygiene , the salivary glands can be infected with bacteria. In these cases, antibiotics are necessary. Also in rare cases, the salivary glands can become blocked, develop tumors, or swell due to the use of certain drugs, such as iodine. A test can be performed to determine whether the person with swelling of the salivary glands actually has the mumps virus.

In late 2002, researchers in London reported the development of a bioassay for measuring mumps-specific IgG. This test would allow a doctor to check whether an individual patient is immune to mumps and allow researchers to measure the susceptibility of a local population to mumps in areas with low rates of vaccination .

Treatment

When mumps does occurs, the illness is usually allowed to run its course. The symptoms, however, are treatable. Because of difficulty swallowing, the most important challenge is to keep the patient fed and hydrated. The individual should be provided a soft diet, consisting of cooked cereals, mashed potatoes, broth-based soups, prepared baby foods, or foods put through a home food processor. Aspirin (only for individuals over the age of 20), acetaminophen , or ibuprofen can relieve some of the pain due to swelling, headache, and fever. Patients should void fruit juices and other acidic foods or beverages that can irritate the salivary glands. They should also avoid dairy products that can be hard to digest. In the event of complications, a physician should be contacted at once. For example, if orchitis occurs, a physician should be called. Also, supporting the scrotum in a cotton bed on an adhesive-tape bridge between the thighs can minimize tension. Ice packs are also helpful.

Prognosis

When mumps is uncomplicated, prognosis is excellent. However, in rare cases, a relapse occurs after about two weeks. Complications can also delay complete recovery.

Prevention

A vaccine exists to protect against mumps. The vaccine preparation (MMR) is usually given as part of a combination injection that helps protect against measles, mumps, and rubella . MMR is a live vaccine administered in one dose between the ages of 12 and 15 months, between four and six years of age, or 11 and 12 years of age. Persons who are unsure of their mumps history and/or mumps vaccination history should be vaccinated. Susceptible healthcare workers, especially those who work in hospitals, should be vaccinated. Because mumps is

still prevalent throughout the world, susceptible persons over the age of one year who are traveling abroad would benefit from receiving the mumps vaccine.

The mumps vaccine is extremely effective, and virtually everyone should be vaccinated against this disease. There are, however, a few reasons why people should not be vaccinated against mumps:

• Pregnant women who contract mumps during pregnancy have an increased rate of miscarriage but not birth defects. As a result, pregnant women should not receive the mumps vaccine because of the possibility of damage to the fetus. Women who have had the vaccine should postpone pregnancy for three months after being vaccinated.
• Unvaccinated persons who have been exposed to mumps should not get the vaccine, as it may not provide protection. The persons should, however, be vaccinated if no symptoms result from the exposure to mumps.
• Persons with minor fever-producing illnesses, such as an upper respiratory infection, should not get the vaccine until the illness has subsided.
• Because mumps vaccine is produced using eggs, individuals who develop hives , swelling of the mouth or throat, dizziness , or breathing difficulties after eating eggs should not receive the mumps vaccine.
• Persons with immune deficiency diseases and/or those whose immunity has been suppressed with anti-cancer drugs, corticosteroids, or radiation should not receive the vaccine. Family members of immunocompromised people, however, should get vaccinated to reduce the risk of mumps.
• The CDC recommends that all children infected with human immunodeficiency disease (HIV) who are asymptomatic should receive an the MMR vaccine at 15 months of age.

Parental concerns

The mumps vaccine has been controversial in the early 2000s because of concern that its use was linked to an increased rate of childhood autism . The negative publicity given to the vaccine in the mass media led some parents to refuse to immunize their children with the MMR vaccine. One result has been an increase in the number of mumps outbreaks in several European countries, including Italy and the United Kingdom.

In the fall of 2002, the New England Journal of Medicine published a major Danish study disproving the hypothesis of a connection between the MMR vaccine and autism. A second study in Finland showed that the vaccine is also not associated with aseptic meningitis or encephalitis. Since these studies were published, U.S. primary care physicians have once again reminded parents of the importance of immunizing their children against mumps and other childhood diseases.

Resources

BOOKS

Gutierrez, Kathleen A. "Mumps Virus." In Principles and Practice of Pediatric Infectious Diseases , 2nd ed. Edited by Sarah S. Long et al. St. Louis, MO: Elsevier, 2003.

Maldonado, Yvonne A. "Mumps." In Nelson Textbook of Pediatrics. Edited by Richard E. Behrman et al. Philadelphia: Saunders, 2004.

Ron Gasbarro, PharmD Rebecca J. Frey, PhD Rosalyn Carson DeWitt, MD