Mumps

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Mumps

Introduction

Disease History, Characteristics, and Transmission

Scope and Distribution

Treatment and Prevention

Impacts and Issues

BIBLIOGRAPHY

Introduction

Mumps is an acute viral illness whose main symptom is parotitis, an inflammation of the salivary glands in the neck. It was first described by the great Greek physician, Hippocrates, in the fifth century BC. Before an effective vaccination program was introduced in 1968, mumps was one of the most significant childhood diseases.

Mumps is as infectious as influenza and rubella (German measles), but somewhat less so than measles and chickenpox. Many of those infected with the virus have no symptoms at all. Mumps usually clears up within a week or so, and those infected then have lifelong immunity. However, the virus can spread through the lymph glands to cause a number of complications, including permanent deafness, so protecting children from mumps through vaccination is important. The introduction of vaccination for mumps has cut the rate of infections in the United States by 98%. However, local epidemics still sometimes occur.

Disease History, Characteristics, and Transmission

Mumps, also known as infectious parotitis, is caused by a paramyxovirus, which consists of single-stranded RNA (its genetic material [ribonucleic acid], as opposed to DNA [deoxyribonucleic acid]) surrounded by a protein envelope. The incubation period of the virus is 12–25 days, during which time it infects the upper respiratory tract and may pass to the glandular tissue of the ovaries, testes, or pancreas through the lymphatic system.

The most common symptom of mumps is parotitis, an inflammation of the salivary glands. The patient will experience pain, tenderness, and swelling in the jaw area, which may be accompanied by an earache. Approximately half of mumps infections are accompanied by parotitis. However, bacterial infection by Staphylococcus species can also cause parotitis, and that may be confused with mumps on diagnosis. Headache is another common symptom of mumps, and malaise, fever, and loss of appetite may also occur, especially in the early stages. Parotitis peaks about two days after its onset and the infection begins to clear within a week, with the vast majority of patients making a full recovery. One attack of mumps confers lifelong immunity, therefore it does not recur.

WORDS TO KNOW

MALAISE: Malaise is a general or nonspecific feeling of unease or discomfort, often the first sign of disease infection.

OOPHORITIS: Oophoritis is an inflammation of the ovary, which happens in certain sexually transmitted diseases.

ORCHITIS: Orchitis is inflammation of one or both testicles. Swelling and pain are typical symptoms. Orchitis may be caused by various sexually transmitted diseases or escape of sperm cells into the tissues of the testicle.

PANCREATITIS: Pancreatitis is an inflammation of the pancreas, an organ that is important in digestion. Pancreatitis can be acute (beginning suddenly, usually with the patient recovering fully) or chronic (progressing slowly with continued, permanent injury to the pancreas).

PARAMYXOVIRUS: Paramyxovirus is a type of virus that contains ribonucleic acid as the genetic material and has proteins on its surface that clump red blood cells and assist in the release of newly made viruses from the infected cells. Measles virus and mumps virus are two types of paramyxoviruses.

PAROTITIS: Parotitis is inflammation of the parotid gland. There are two parotid glands, one on each side of the jaw, at the back. Their function is to secret saliva into the mouth.

REPORTABLE DISEASE: By law, occurrences of some diseases must be reported to government authorities when observed by health-care professionals. Such diseases are called reportable diseases or notifiable diseases Cholera and yellow fever are examples of reportable diseases.

RIBONUCLEIC ACID (RNA): Any of a group of nucleic acids that carry out several important tasks in the synthesis of proteins. Unlike DNA (deoxyribonucleic acid), it has only a single strand. Nucleic acids are complex molecules that contain a cell's genetic information and the instructions for carrying out cellular processes. In eukaryotic cells, the two nucleic acids, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA), work together to direct protein synthesis. Although it is DNA (deoxyribonucleic acid) that contains the instructions for directing the synthesis of specific structural and enzymatic proteins, several types of RNA actually carry out the processes required to produce these proteins. These include messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). Further processing of the various RNAs is carried out by another type of RNA called small nuclear RNA (snRNA). The structure of RNA is very similar to that of DNA, however, instead of the base thymine, RNA co

However, mumps does sometimes cause complications and, indeed, is responsible for one death a year, on average, in the United States. When the virus spreads to the glands, it can cause orchitis (inflammation of the testicles), oophoritis (inflammation of the ovaries), pancreatitis, arthritis, and encephalitis. Central nervous system involvement in the form of asymptomatic meningitis is common, while symptomatic meningitis with headache and stiff neck occurs in up to 15% of patients, although this usually resolves itself within several days. Around one in 10,000–20,000 cases of mumps will lead to permanent deafness, with sudden onset. In 80% of these cases, the deafness is confined to one ear.

The mumps virus is spread by airborne transmission and through the droplets created by coughs and sneezes. Those infected will spread the virus about a week before they develop symptoms—if any occur—and will remain infectious for up to ten days after the symptoms begin. People without symptoms may still be infectious.

Scope and Distribution

The mumps virus affects both children and adults around the world, with the peak of infection occurring in late winter and early spring, although cases occur throughout the year as well. However, mass vaccination has had a dramatic impact on the number of cases of mumps where it is used. In World War I (1939-1945), only gonorrhea and influenza caused more hospitalizations than mumps among the military.

When it comes to the complications of mumps, adults appear to be more susceptible than children. Men in the 15–29 age group are the most susceptible to orchitis, which affects 20–50% of those developing mumps. In 30% of these cases, both testicles are affected, which raises the threat of infertility. However, although shrinkage of the testicles does occur in some cases of orchitis, infertility rarely results. Around 5% of young women with mumps will develop oophoritis, which may cause severe pelvic pain, but this complication is not linked to infertility. Pregnant women who develop mumps run an increased risk of spontaneous abortion. Mumps has been a reportable disease in the United States for several years.

IN CONTEXT: SCIENTIFIC, POLITICAL, AND ETHICAL ISSUES

With regard to a potential connection between the measles, mumps, and rubella vaccine (MMR vaccine) and autism, scientists at the National Immunization Program (NIP) at Centers for Disease Control and Prevention (CDC) state that “the weight of currently available scientific evidence does not support the hypothesis that MMR vaccine causes autism. CDC recognizes there is considerable public interest in this issue, and therefore supports additional research regarding this hypothesis. CDC is committed to maintaining the safest, most effective vaccine supply in history.”

As of May 2007 the CDC further states that, “there is no convincing evidence that vaccines such as MMR cause long term health effects. On the other hand, we do know that people will become ill and some will die from the diseases this vaccine prevents. Measles outbreaks have recently occurred in the UK and Germany following an increase in the number of parents who chose not to have their children vaccinated with the MMR vaccine. Discontinuing a vaccine program based on unproven theories would not be in anyone's best interest. Isolated reports about these vaccines causing long term health problems may sound alarming at first. However, careful review of the science reveals that these reports are isolated and not confirmed by scientifically sound research. Detailed medical reviews of health effects reported after receipt of vaccines have often proven to be unrelated to vaccines, but rather have been related to other health factors. Because these vaccines are recommended widely to protect the health of the public, research on any serious hypotheses about their safety are important to pursue. Several studies are underway to investigate still unproven theories about vaccinations and severe side effects.”

SOURCE: Centers for Disease Control and Prevention, National Immunization Program

Treatment and Prevention

Treatment of mumps infection includes hydration and painkillers. If headache is severe, then lumbar puncture may bring relief. Strong painkillers may be needed in cases of orchitis, because the pain can be quite severe. Children and adults with mumps should be excluded from school or work during the infectious period.

Mumps can be prevented by immunization with a live mumps vaccine. This is part of the measles, mumps and rubella (MMR) vaccine, which is given as childhood immunization—once at 12–15 months and again between four and six years of age. Although the mumps vaccine is generally safe, it should not be given to pregnant women, those with a fever, or patients with weakened immunity. There have been occasional side effects of mumps vaccine on the central nervous system, some of which have led to deafness. As with all airborne diseases, good personal hygiene helps prevent transmission. Therefore, people should always cover their nose and mouth when they cough or sneeze, and wash their hands regularly.

Impacts and Issues

Mumps was once a major childhood disease with occasional serious complications, such as deafness and infertility. Vaccination has changed that. Mumps became a reportable disease in the United States in 1968, when vaccination was introduced. Before that, there were an estimated 212,000 cases per year. However, between 1983 and 1985, there were only around 3,000 cases reported annually, demonstrating the value of mass vaccination.

In 1986 and 1987, there was a relative resurgence of mumps, with around 13,000 cases being reported in the United States. Most occurred in the 10–19 age group, who were born before vaccination was introduced. Since mumps can affect adults too, this was not unexpected. There were several outbreaks among highly vaccinated school populations, which suggested that a single dose might not be sufficient to protect children.

Since 1989, there has been a marked decline in the number of reported cases of mumps, from 5,712 cases to a total of 258 cases in 2004. But childhood infections like mumps can still come back unexpectedly. In 2006, there were outbreaks in several states, mostly among young adults, which led to a total of more than 6,000 reported cases. Most of these cases had received either one or two shots of MMR, but possibly had not developed a full immune response for some reason.

Introduction of mumps vaccine has been associated with a shift in the age at which people get the disease. Previously, 90% of cases occurred among children aged 15 or younger. But since 1990, those aged 15 or older have accounted for 30–40% of cases each year, with males and females being affected equally. These trends may reflect the effect of vaccine coverage in the population, and also the tendency of mumps to affect both children and young adults. Mumps is a disease that should not be taken lightly. Any lapse in vaccination coverage could lead to more outbreaks, with the attendant—albeit rare—complications.

See AlsoChildhood Infectious Diseases, Immunization Impacts; Measles (Rubeola); Rubella.

IN CONTEXT: SOCIAL AND PERSONAL RESPONSIBILITY

Social issues can still arise out of even the most effective and seemingly well-intended of medical advances. For example, although childhood diseases such as measles, mumps, whooping cough, and diphtheria have been effectively controlled by childhood vaccinations, some parents resist or reject vaccinating their own children because they feel that the small personal risk is not mitigated by the larger social benefit of disease control. By opting out of the system (by relying on the immunizations of others to reduce the risk of disease) they rely upon the acts their social group to offer their open children personal protection.