Vaccination

An infection happens when a "microorganism" (a living thing so small that we can't see them individually) begins to grow and multiply in the body. We all have millions of microorganisms on and in our bodies. There are many bacteria (microorganisms that can live independently) on our skin, and even more in our intestines and mouths. These bacteria are not only fairly harmless (unless your immune system isn't working quite right) but actually help you out. However, there are many bacteria that will make you sick. Some are usually not found in the body unless you are sick. In other cases, normally harmless or helpful bacteria may overgrow or invade parts of the body where they aren't supposed to be.There are also viruses, particles that cannot live by themselves but which can invade your body's cells, take over those cells' growth machinery, and make the cells start producing more virus particles.

Vaccines are given at an early age because the diseases they prevent can strike at an early age. Some diseases are far more serious or common among infants or young children. For example, up to 60% of severe disease caused by Haemophilusinfluenzae type b occurs in children under 12 months of age. Again, the age at which a particular vaccine is given to your child also depends upon the geographical area and that county’s health care policy, and this will in turn depend on the prevalence of a particular disease in that area/country.

They can continue the series where they left off. Vaccinations are not rendered invalid and do not have to be repeated when there is a longer-than-recommended interval between doses in a series.

They are very safe. But like any medicine, they are not perfect. They can cause reactions. Usually these are mild, like a sore arm or slightfever. Serious reactions are very uncommon. Your health-care provider will discuss the risks with you before your child gets each vaccine. The important thing to remember is that vaccines are much safer than the diseases they prevent.

Vaccines work most of the time, but not always. Most childhood vaccinations work between 90% and 100% of the time. Sometimes, though, a child may not respond to certain vaccines, for reasons that aren’t entirely understood.