Trudy Ann Hinds
CNB

Disease

Mumps

Causative agent

The cause of Mumps is an infection with the Mumps virus.  Mumps is a single-stranded, enveloped, negative-sense RNA virus in a helical nucleocapsid (def) structure.  The Mumps virus belongs to the family Paramyxoviridae, genus Paramyxovirus.  They range in sizes 150-300 nanometers (def) of helical symmetry.  Mumps mainly affects humans and considered less contagious than both measles (def) and chickenpox (def).  The virus also has a high sensitivity to ultraviolet light and heat.

Epidemiology

Due to active immunization against the Mumps virus since 1968, infections are rare in the United States and other developed countries.  The United States reported more than a 50 percent reduction in incidence rate per 100, 000 of the population in persons aged 10 years or older in recent years.  According to reports by the Centers for Disease Control and prevention (CDC), in 2003 there were less than 300 cases in the United States.  However, Mumps virus is still prevalent in some third world countries, which do not administer the measles, mumps, and rubella MMR vaccine among children and young adults.

Mumps can also cause meningitis (def) encephalitis (def), pancreatitis (def) and hearing loss or deafness at any age.  In addition, Mumps encephalitis (def) and infertility are 3-5 times more frequent in males than females; nevertheless, the Mumps virus has no sexual preference.  Death is very unusual and the illness is self- limiting (def) without any harmful complications and usually induces lifelong immunity.  More fatality occurs in persons older than 19 years old.  The infection was more prevalent amongst blacks especially in the age range 5-19 years old and lowest for Hispanics among the same age group.

Only one type serotype of the virus exists.  Consequently, about 20-30 percent of mumps infections are asymptomatic (def) and do not develop typical signs of swelling in the face and neck.  Instead, infected persons may develop upper respiratory symptoms similar to the common cold.  During this phase, persons can easily spread the virus without knowing it.  Mumps is most frequent during spring, especially between Januarys to May in urban areas, concentrated with large numbers of children and young adults.  However, in tropical countries there are no seasonal differences.

Transmission

The virus is contagious and transmitted through salvia and respiratory secretions from person-to-person.  Mumps portal of entry is the respiratory tract and stays in the mucus of the nose and throat as well as the saliva of the infected person.  Common transmission of the virus includes sneezing and coughing, whereby the aerosolized respiratory droplets enter the eyes, nose, and mouth of another person.  Infections can also spread by sharing food, drinks, and kissing plus contact with contaminated surfaces with the virus.

Signs and Symptoms

The Mumps virus is characterized by inflammation, swelling of the parotid glands (def) on one or both sides, fevers, vomiting, and pain during swallowing.  The virus develops in the respiratory tract and then local lymph nodes in the neck, finally reaching the salvia via the blood.  Once in the blood the virus can spread heart, thyroid, testes, and ovaries along to the meninges membrane (def) of the brain and spinal cord.  Viremia (def) is present before the onset of Mumps symptoms and before the virus appears in salvia.  The virus is present in the blood and saliva for 6 days before the onset of the symptoms and in the urine for about 10 days after noticeably symptoms occurs.  In total the incubation period (def), can last about 16-18 days.  Males past puberty may develop a condition called orchitis (def) about 4-7 days after the onset of symptoms and in rare cases testicular atrophy (def) and sterility (def).  While in about 5 percent of adolescent and adult females may develop oophoritis (def) although it does not affect their fertility. Less common symptoms can also occur such as headaches, malaise (def), myalgia (def) dry mouth sore face, and sore ears.  The most common systemic complications include Transient high frequency deafness (def) and permanent unilateral deafness (def) with incidence rates of 4 percent and less than 1 percent respectively.  A confirmation of diagnosis is mainly based on physical examination of the swollen glands and not on clinical grounds such as laboratory testing.

Prevention and Treatment

The most effective and preventative measure against Mumps is immunization with the Mumps vaccine.  The measles, mumps, and rubella MMR vaccine is an effective attenuated live vaccine that is often administer or given separately to immunize against the mumps virus.  Unpleasant side effects are uncommon with the vaccine and the protection rate is over 95 percent.  The mechanism by which the vaccine works is by producing cell-mediated and humoral antibodies for future resistance.  Routine mumps vaccines are used in all countries with an active childhood vaccination program based on recommendations from the WHO (World Health Organization).  Other clinical recommendations includes administration of MMR vaccine at ages 12-15 months and a second dose of the vaccine is recommended at age 6-13 years of age in many countries.  The Jeryl Lynn and Leningrad-Zagreb are the two common strains used in developed countries.  Other than vaccine, frequent hand washing, cleaning of contaminated surfaces, and limited contact with infected individuals is also recommended.

There are no specific treatment recommended in infants and children except the control of symptoms with painkillers.  Supportive care (def) is best to relive symptoms by warm salt gargles, soft foods, and extra fluids, with the exception acidic foods that may induce pain in the salivary glands.  The use ice or heat to the swollen and affected areas may prove beneficial in relieving pain.  Otherwise, the infection is allowed to run its course within the body and recede.
 
Bibliography

Demirci, Cem Abuhammour, Walid. Mumps. Retrieved April 6,  2010 from. http://emedicine.medscape.com/article/966678-overview.
Mumps. 2006-2010 by eMedTV.  Retrieved April 6, 2010 from http://mumps.emedtv.com/mumps-virus/mumps-virus.html.
Mumps. Www.wikipedia.org. 2010.  Free Encyclopedia. Retrieved April 6,  2010 from http://en.wikipedia.org/wiki/Mumps_a_virus.
Wong, Derek.  Welcome to Wong's Virology . Viruses. Mumps virus. Retrieved April 6,  2010 from http://virology-online.com/viruses/MUMPS.htm
Mumps virus. The University of Texas Medical Branch at Galveston. 1996 Retrieved April 6, 2010 from  http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=mmed&part=A3150.