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Mumps
(Infectious parotitis)
Mumps
• Acute viral illness
• Parotitis and orchitis described by Hippocrates
in 5th century B.C.
• Viral etiology described by Johnson and
Goodpasture in 1934
• Frequent cause of outbreaks among military
personnel in prevaccine era
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What is mumps?
It is a disease caused by the mumps virus.
Who gets mumps?
Past infection with mumps makes a person
immune to mumps; most people born before
1957 most likely have already had mumps. In
addition, people who receive two doses of the
mumps vaccine are much less likely to be
infected. The greatest risk of infection occurs
among older children, adolescents, and
adults.
Mumps Virus
• Paramyxovirus
• It is a single-stranded RNA virus
• One antigenic type
• Rapidly inactivated by chemical agents
(formalin, ether, chloroform), heat and
ultraviolet light.
• How is mumps spread?
• Mumps is spread in droplets from the nose or
throat of an infected person, usually when a
person coughs or sneezes. Mumps can also
spread by direct contact with saliva and
discharges from the nose and throat of an
infected person.
Mumps Clinical Features
• Incubation period 14 - 18 days
• Nonspecific prodrome of low-grade fever,
headache, malaise, myalgias
• Parotitis in 30% - 40%
• Up to 20% of infections asymptomatic
• May present as lower respiratory illness,
particularly in preschool-aged children
• About one in three persons infected with
mumps virus do not have any signs or
symptoms of illness. The most common signs
and symptoms of mumps include fever,
headache, and swelling and tenderness of one
or more salivary glands. Swelling of the
testicles occurs in 20-30% of infected males this does not usually result in sterility.
• Mumps can also cause central nervous system
disorders such as encephalitis (inflammation
of the brain) and meningitis (inflammation of
the covering of the brain and spinal column).
Other complications include miscarriage of a
pregnancy, arthritis, pancreatic involvement,
or deafness.
• How soon after infection do signs and
symptoms occur?
• Signs and symptoms of mumps usually appear
within 18 days after exposure, but may appear
any time within 12 to 25 days after exposure.
• When and for how long is a person able to
spread mumps?
• Mumps is contagious from three days before until
five days after the onset of swelling.
• What is the treatment for mumps?
• Supportive care to relieve symptoms may include
applying intermittent ice or heat to the affected
neck area, and pain relievers. Warm salt water
gargles, soft foods, and extra fluids may also help.
Avoid fruit juice or acidic foods, since these
stimulate the salivary glands, which can be
painful.
Mumps Complications
CNS involvement
15% of clinical cases
Orchitis
20% - 50% in postpubertal males
Pancreatitis
2% - 5%
Deafness
1 / 20,000
Death
1 - 3 / 10,000
Mumps Epidemiology
• Reservoir
Human
• Transmission
Respiratory drop nuclei
Subclinical infections
may transmit
• Temporal pattern
Peak in late winter and spring
• Communicability
Three days before to five
days after onset of active
disease
• During adulthood, infection is likely to
produce more sever disease including orchitis.
• Death attributable to mumps is rare, the
estimated case fatality rate is 3.8 per 10000.
more than fatalities occur in people older than
19 years of age.
• Mumps infection during the first trimester of
pregnancy is associated with an increased risk
of spontaneous abortion.
• There is no evidence exists that mumps infection
during pregnancy causes congenital
malformations.
• Peak incidence was between January and May
• Treatment: Supportive
• Isolation of the hospitalized patient: in addition
to standard precautions, droplet precautions are
recommended until 9 days after onset of parotid
swelling.
• Control Measures:
1- School and child care : children should be
excluded for 9 days from the onset of parotid
swelling
2- Care of exposed people: vaccine not effective
in preventing infection after exposure.
However mumps vaccine can be given after
exposure, because Immunization will provide
protection against subsequent exposure.
.Immunization during the incubation period
has no increased risk. Mumps Ig is of no value
• Mumps Vaccine:
This is generally given as measles-mumpsrubella (MMR) vaccine. MMR is usually given
on or after a child's first birthday. A second
vaccination is recommended, again in
combination with measles and rubella
vaccine, at 4-6 years of age. Persons of any
age who are unsure of their mumps disease
history and/or mumps vaccination history
should be vaccinated, especially if they are
likely to be exposed.
Mumps Vaccine
• Composition
Live virus
• Efficacy
95% (Range, 90% - 97%)
• Duration of
Immunity
Lifelong
• Schedule
2 Doses (as MMR)
• Should be administered with measles and rubella (MMR)
Mumps Vaccine (MMR) Indications
• All infants >12 months of age
• Susceptible adolescents and adults
without documented evidence of
immunity
Second Dose Recommendations
• First dose of MMR at 12-15 months
• Second dose of MMR at 4-6 years
• Second dose may be given any time >4 weeks
after the first dose
Second Dose of MMR Vaccine
• Intended to produce immunity in persons
who failed to respond to the first dose
(primary vaccine failure)
• The second dose of MMR is recommended to
produce immunity in those 2-5% who failed
to respond the first dose. It’s not technically
a booster dose, although the second dose
may also boost antibody titers in some of
those who did respond to the first dose.
• What can be done to prevent the spread of
mumps?
• The single most effective control measure is
maintaining the highest possible level of
immunization in the community.
• Children with mumps should not attend school,
and adults should not work, until five days after
swelling began or until they are well, whichever is
longer. Measures such as covering coughs and
sneezes, washing hands frequently, and not
sharing food or eating utensils can also help. A
person who may have had contact with a mumps
case should be evaluated by their physician.
However
• High MMR vaccine coverage levels and
vaccine effectiveness likely prevented
thousands of additional mumps cases (9 out
of 10 exposures that may have resulted in
infection in 2 dose vaccinees prevented)
• Incidence relatively low
• Disease may be modified
Adverse Reactions:
febrile seizures, nerve defness,meningitis,
encephalitis, rash ,pruritis .orchitis and
parotitis have been reported rarely.
Precautions and Contraindications:
1- Febrile illness: fever is not contraindication to
immunization . However if other
manifestations suggest a more serious illness ,
the child should not be immunized until
recovered .
• 2-Allergies
• 3- Recent administration of immune globulin: because
high dose of Ig can inhibit the response to measles
vaccine for longer intervals , MMR immunization
should be deferred for a longer period after
administration of IG.
• 4- Altered immunity : patients with immunodeficiency
diseases or people receiving immunosuppressive
therapy except patients with HIV infection.
• 5. Corticosteroids: the recommended interval is at least
one month after steroids is discontinued.
• Pregnancy: live – virus mumps vaccine can infect the
placenta but the virus has not been isolated from fetal
tissue
However conception should be avoided for 28
days after mumps immunization.
• Out break control :
• Exclusion of susceptible students from
affected schools judged by local public health
authorities to be at risk of transmission should
be considered.