Measles Prevention

Dr. Parang Mehta, MD.

Measles is the most infectious diseases known. It has a secondary attack rate of nearly 100% -- all the children exposed to a child with measles will get the disease, if they are not immune to measles. Other diseases that are so highly infectious are pertussis (whooping cough) and varicella (chicken pox).

Spread of Measles

Measles spreads mainly through the air. The droplets coughed and sneezed by children with the infection contain the measles virus, and these infect the people breathing in the same air. Measles can spread rapidly and widely in places like classrooms and day care centres.

A major problem is that the disease is infective for a few days before the rash appears. This means that children with measles attend school or daycare for a day or two before they are diagnosed and isolated. For the individual child, personal protection by vaccination is the only reliable preventive method.

The Measles Vaccine

The measles vaccine was made from measles virus obtained from a child named Edmonston. It was licensed for use in America in 1963, and quickly brought down the number of cases by 98%. As of today, most developed countries have controlled this disease. The US has around a hundred cases a year, most of them imported (infection acquired by travellers to foreign countries).

The measles vaccine is a live virus vaccine. Injecting a child with this vaccine causes a mild form of the measles illness. This is usually so mild, that it goes unnoticed. A few children develop some feever and/or a scanty rash.

This mild infection, however, is adequate to stimulate the immune system of the body. The cells of the immune system get acquainted with the measles virus, and learn to produce antibodies to it.

When should it be given?

The timing is very important. Children are born with immunity to measles, thanks to antibodies passed from their mothers. Because of this, the vaccine is not able to cause the mild infection it normally does. Without this, the cells of the immune system do not get exposed to the virus, and do not learn to recognise it and produce the specific antibody.

The maternal antibodies persist in the child's body for a variable period, lasting from 6 months to 15 months. Vaccine given before the antibodies have disappeared from the bloodstream is likely to be unsuccessful.

The American Academy of Pediatrics (AAP) and the Centers for Disease Control (CDC) recommends that all children receive 2 doses of the measles vaccine after they are 12 months of age. These doses can be given as the MMR vaccine, which contains, in addition, vaccines against the mumps and rubella (german measles) viruses.

However, sometimes children below the age of 12 months are at high risk for developing measles. This may be because of an outbreak in the region, or cases in the home. In such situations, children as young as 6 months can be given the vaccine.

Many of these children will have persisting maternal antibodies, which will prevent the effect of the vaccine. However, the same antibodies will also protect the child against measles. Children who have lost the maternal antibodies will develop antibodies after the vaccine. All children vaccinated early should be given a second dose of the measles vaccine at a later age.

Measles in Children

 

Last revision: September 16, 2011

If your child is exposed to measles

It happens sometimes -- a child in school or the daycare center is diagnosed with measles. Your child has spent several hours in the same room, and measles is highly infectious. What needs to be done to avoid this diesease?

If your child is vaccinated against measles, nothing. The vaccine has induced immnunity at the time it was given, and the memory remains. When measles virus enters the body, the immune system cells produce antibodies and neutralise it. The child does not get measles.

If your child is less than a year old, and has never received the measles vaccine, you should see your pediatrician. The measles vaccine can be given at younger than recommended ages also, if a child is at rist for measles. The vaccine can be given to children as young as 6 months of age.

if your child is older than a year, but is still unimmunised, the measles vaccine should be given. Even when given after exposure, the vaccine is able to provide some protection. The child may not get measles, or may have mild disease.

Contact Information

Dr. Parang Mehta,
Mehta Childcare,
Opposite Putli, Sagrampura,
Surat. Tel: +91 98241 53923.
Email: