The Measles Vaccine

Dr. Parang Mehta, MD.

Measles is a viral disease, and there is no known treatment for it.  The measles vaccine is the only measure we have to protect children against the disease.  Before the vaccine came into use, the worldwide death toll caused by measles was around five million per year, mostly children.  Even today, the disease causes about a quarter of a million deaths a year -- think of it as 700 a day, or 27 children dying every hour, to appreciate the importance of the measles vaccine.  

Measles is the most infections disease known, with a secondary attack rate of nearly 100%.  Almost all susceptible people who come in contact with a person with measles will develop the disease.  Vaccination is thus vitally important.  The measles vaccine has been in use for over fifty years, and is a safe and effective vaccine.

The Measles Vaccine

The measles vaccine was first used in 1963.  At that time, both a killed and a live vaccine were tried out.  The killed vaccine was found to be ineffective, and only the live vaccine has been in use.  There are many strains of the vaccine virus in use - the Schwarz, the Edmonston B, the Edmonston Enders (also known as Moraten).

Measles vaccine is available both as a single vaccine, and in combination with the mumps and rubella vaccines (the MMR vaccine).  A recent introduction is the combinaiton of MMR with the chicken pox (varicella) vaccine.

The measles vaccine, being a live virus, sets up an infection in the body.  Since the vaccine viruses have been carefully weakened, this infection does not make the child sick, but stimulates the immune system, giving the child immunity to measles.

To reduce the number of injections, measles vaccine can be given as one of the combinations, after the age of 12 months.  More than 95% of children will develop immunity after a single dose.  Vaccine failure may be caused by measles antibody from the mother persisting in the blood, damaged vaccine, or other causes.  More than 99% children develop long term immunity after 2 doses.

Side Effects

Side effects are not very severe - it is, in general, a safe vaccine.  The most common side effect is fever.  A rash, similar to measles occurs in a small percentage of recipients.  The rash, and/or fever usually occur a week after vaccination, and last 2-4 days.

Allergic reactions to the vaccine and its components occur in some children.  Children with severe reactions should not receive further doses.

Rare side effects are joint pains, reduction in blood platelets (thrombocytopenia), and enlargement of the lymph nodes (lymphadenopathy).

Contraindications

Last Revision: February 11, 2016

Measles Vaccine -- Timing is Everything

Most women have had either measles, or the measles vaccine, at some time in their lives.  They have antibodies against measles in their blood, and these pass through the placenta to the baby during the last weeks of pregnancy.  Thus, most babies are born with immunity to measles (and several other diseases).

These antibodies persist in the blood for 6 to 15 months, varying from child to child.  As long as they are present, the measles vaccine, if given, is unable to act.  Ideally, therefore, we should give the vaccine at 15 months of age, when we are sure there will be no antibodies left.  This is what is done in most countries.

In countries where measles is widespread, children have a high chance of getting it if left unvaccinated for 15 months.  Since Measles is often severe in young children, the vaccine is recommended at the age of 9 months in countries like India.  We assume that most children will have lost their maternal antibodies by this age, and will develop immunity to measles after the vaccine.  During an epidemic of measles, the vaccine is sometimes given to children as young as six months of age.

These children should receive a second dose of measles, or of the MMR (measles, mumps and rubella) vaccine at the age of 15 months.  This second dose of measles vaccine will cover those few children who did not benefit from the 9 month dose.

Children who have received a single dose of measles or MMR vaccine around or after the first birthday should receive a second dose at 4-6 years of age.  Children who have not been vaccinated should receive 2 doses, separated by at least 4 weeks.
 

Contact Information

Dr. Parang Mehta,
Mehta Childcare,
Opposite Putli, Sagrampura,
Surat, India.    Tel: +91 9429486624.
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