Saturday, February, 11, 2012

Immunizations - general overview

Table of Contents

  • They expose you to a very small, very safe amount of a virus or bacteria that has been weakened or killed.
  • Your immune system then learns to recognize and attack the infection if you are exposed to it later in life.
  • As a result, you will either not become ill or have a milder infection. This is a natural way to deal with infectious diseases.

Four different types of vaccines are currently available:

  • Live virus vaccines use the weakened (or attenuated) form of the virus. The measles, mumps, and rubella (MMR) vaccine and the varicella (chickenpox) vaccine are examples of this type.
  • Killed (inactivated) vaccines are made from a protein or other small pieces taken from a virus or bacteria. Influenza shots are an example of this type of vaccine.
  • Toxoid vaccines contain a toxin or chemical made by the bacteria or virus. They make you immune to the harmful effects of the infection, instead of to the infection itself. Examples are the diphtheria and tetanus vaccines.
  • Biosynthetic vaccines contain human-made substances are very similar to pieces of the virus or bacteria. The Hib (Haemophilus influenzae type B) conjugate vaccine is one example.

WHY WE NEED IMMUNIZATIONS

Newborns, babies, and toddlers are constantly being exposed to germs from their parents, other adults, brothers and sisters, people in stores, and other children in child care. With travel easier than ever, you and your baby can be exposed to diseases from other countries without you knowing.

For a few weeks after they are born, babies will have some protection, which was passed from their mother through the placenta before birth. After a short period of time, this natural protection goes away.

Immunizations help protect infants, children, and adults against many infections that used to be much more common.

  • Examples include tetanus, diphtheria, mumps, measles, pertussis (whooping cough), meningitis, and polio.
  • Newer immunizations protect children and adults against other types of meningitis, pneumonia, and ear infections.

Many of these infections can cause serious or life-threatening illnesses, and may lead to lifelong disabilities. Because of immunizations, all of these illnesses are now rare.

SAFETY OF IMMUNIZATIONS

Many parents are worried that some vaccines are not safe and may harm their baby or young child. They may ask their doctor or nurse to wait, or even refuse to have the vaccine. However, it is important to also think about the risks of not having the vaccination.

Some people believe that vaccines cause autism or ADHD. They are worried that a small amount of mercury (called thimerosal) that is used as a preservative in multidose vaccines will cause these problems. Multidose means that many doses of vaccine come in one bottle.

However, studies have NOT shown this risk to be true.

  • Experts such as The American Academy of Pediatrics, and The Institute of Medicine (IOM) agree that no vaccine or part of any vaccine is responsible for the number of children who are currently being diagnosed with autism.
  • They conclude that the benefits of vaccines outweigh the risks.

Review Date: 12/15/2010
Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)