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MMR vaccine for measles,
mumps and rubella
Paul R. Earl
Facultad de Ciencias Biológicas
Universidad Autónoma de Nuevo León
San Nicolás, NL, Mexico
Measles is a highly contagious viral
childhood disease that affected almost
everybody during the prevaccination era.
Measles is an RNA negative strand virus
belonging to the Mononegavirales of the
family Paramyxoviridae. Transmission is
primarily by large yet invisible respiratory
droplets. The disease typically consists of a
high fever, cough, runny nose and a classic
rash. Complications such as diarrhea, middle
ear infection and pneumonia occur. Infants
under one year of age have the highest case
fatality rates reaching as high as 20% in
epidemics.
Regardless, as children are vaccinated for
1/ measles, 2/ mumps and 3/ rubella
(German measles) with the same vaccine—
MMR—these 3 diseases are taken up
together.
The MMR vaccine prevents 3 childhood
diseases — measles, mumps and rubella.
Measles is best known as an illness with
rash and high fever, but can also lead to
pneumonia or encephalitis and can cause
death. Approximately 5% of children with
measles will develop pneumonia and more
than 3 out of 10,000 can die.
Mumps
is a disease caused by the mumps
virus. It usually infects children younger than
10 years old and begins with swelling of the
salivary glands. The swelling usually lasts for
about a week. Mumps can cause deafness, an
infection of the lining of the brain
(meningitis) and even death.
Rubella is usually not a serious disease for
children but it almost always causes birth
defects when a pregnant woman is infected.
Up to 85% of babies whose mothers are
infected during pregnancy will have
blindness, deafness, heart defects or mental
retardation.
The vaccine effectively protects against all 3
diseases in at least 95% of children who
receive 2 shots. Nearly all children who get the
MMR vaccine (more than 80%) will have no
side effects at all. Of those children who have a
side effect, most will have only a mild reaction.
Mild side effects of the vaccine include
soreness, redness or swelling where the shot
was given, mild rash, mild to moderate fever,
swelling of the lymph glands and temporary
pain, stiffness or swelling in the joints. In about
0.03% of cases) children have a moderate
reaction. This reaction is a seizure related to
having a high fever. Ony 0.001% of children
have a serious reaction.
Regardless, the costs of MMR or other
immunizations is the obstacle. The results of
benefit–cost analyses may be at 3-6 times, yet
difficult to assess in rural countries. Local
estimates of disease burden, costs of treatment,
costs of vaccination, and the rates of adverse
events for the vaccine strain of interest. Some
countries as in Africa use monovalent measles
vaccine to save money. In other cases like Peru,
the government will not spend the money for a
healthier country. It is quite obviously
important that all national health stations
function well with adequate personel and
supplies, not true for India which has 1000
million people nor for many other countries.
Despite the availability of measles vaccine for the
last 3 decades globally, WHO reported 30 million
cases of measles with 880,000 deaths in 1998. Of
these 85% occur in SE Asia. The coverage figures
for measles vaccination have steadily increased and
stayed at around 85-90% since 1990. All vaccine
percent for India in 2000 was 42%. There is a gap
between the official figures and the real coverage.
The coverage is especially poor in the rural areas, in
tribal populations and inaccessible populations. This
has lead to outbreaks of considerable severity.
Measles causes substantial mortality, disruption in
services, and continues to be a major drain on
resources. Epidemics of the disease continue to
occur because of poor coverage and an inefficient
surveillance system.
The WHO/UNICEF Global
Measles Strategic Plan 2001–
2005 seeks to reduce measles
mortality worldwide in a
sustainable way by 50%
relative to 1999 estimates.
WHO=OMS is World Health
Organization = Organización
Mundial de Salud.
Administration Summary. a) Type of
vaccine: Live attenuated viral, b) Number of
doses: One dose given by the intramuscular or
subcutaneous route, with opportunity for a
second dose at least one month after the first.
c) Schedule: At 9–11 months of age,
d) Booster: A second opportunity for
immunization is most strongly recommended.
e) Contraindications: Severe reaction to
previous dose; pregnancy; congenital or
acquired immune disorders. f) Adverse
reactions: Malaise, fever, rash 5–12 days later;
idiopathic thrombocytopenic purpura; rarely,
encephalitis or anaphylaxis.
Mumps is an acute infectious disease caused by
a paramyxovirus closely related to parainfluenza
virus. The disease is usually mild and about onethird of cases are asymptomatic. Up to 10% of
mumps patients developed aseptic meningitis.
A less common but more serious complication is
encephalitis which can result in death or
disability, including permanent deafness, orchitis
and pancreatitis. As of mid1998, mumps vaccine
was routinely used by national childhood
immunization programs in 82 countries. Where
high coverage has been achieved, countries have
shown a rapid decline in mumps morbidity
especially the near elimination of encephalitis.
Rubella. Attention was called to this mild
disease in 1942 when Norman Gregg found
that first-trimester maternal rubella caused
serious birth defects. Much embryopathy was
clarified groups: Parkman, Buescher &
Artenstein, and Neva & Weller. The severe
rubella epidemic of 1964 affected about 1%
of pregnancies. Signs neonatal
thrombocytopenic purpura, hepatitis, bone
lesions and meningoencephalitis as well as
late-emerging consequences like diabetes
mellitus and progressive rubella
panencephalitis also with cataract, heart
disease, mental retardation and deafness.
Rubella is passed on by direct contact, and
by coughing and sneezing the virus into the
air. It takes 2-3 weeks to develop
symptoms after being infected. Persons are
infectious from 1 week before symptoms
begin until 5 days after the rash appears.
Therefore, affected children should stay
away from school and not mix with others
for 5 days after the rash starts. Most
women are immune due to previous
immunization and will not develop rubella.
No further action is needed if patients are
known to be immune.
Eradication of many diseases is currently
possible as demonstrated by the conquest of
smallpox and polio. Most of these diseases
are not technically difficult. The persons who
insist that they are have been so informed or
brainwashed by higherups who in their turn
cannot find the money that is needed for
some eradication. If the money does show up,
perhaps by magic or the World Bank, it may
quietly disappear—anyway. MMR is currently
underdosed and undercovered, mainly
because of governments too chinzy with their
money, except for the Afroasian poor.