To learn about how vaccines work in other countries, read Vaccinations Around the World.

How is a vaccine manufactured? Most vaccines are made up of the microbe strain it wants to protect against. I’ll explain. Through research, we now know that we can prevent illness by giving a tiny amount of a microbe to a human. This will stimulate their immune system and create antibodies, but not enough to cause the illness.

In a vaccine, you can find a small amount of dead or weakened bacteria or virus. There are also cloned vaccines, which are synthetic and imitate the pathogenic agent responsible for the illness. This will activate the immune system defence in a human.

Additionally, to minimise the number of injections, researchers have designed vaccines that combine more than one strain of bacteria or virus at a time. Doing so makes the immune system react in the same way as if it was administered a single vaccine. It also doesn’t multiply the undesired reactions for the person who received the vaccine. This is the case for the vaccine that combines diphtheria, tetanus and whooping cough, which combines three different vaccines mixed together. One needle is always better than three, right?

Some parents wonder if they can choose the individual vaccines given to their baby. It’s impossible to inject the range of vaccines found in the immunisation schedule in a single dose. Some vaccines can be given alone, but often in an adult dose, not in a pediatric dose.

The Immunisation Process—Building Defences

Here is the process for building antibodies from the arrival of a bacteria or virus during an illness or vaccine administered to the body:

1.  Invasion of an illness (bacteria or virus) either via the airways, digestion, intestines, skin, etc. or by an injected, inhaled or oral vaccine;
2. This activates the body’s immune defence system, which manufactures antibodies;
3. Vaccines stimulate the manufacture of antibodies in 90-95% of cases if given when recommended. Some people’s immune system won’t react well and will produce insufficient or no antibodies. We still don’t know why;
4. Antibodies remain in the body for a variable length of time based on the type of vaccine. This is why some vaccines must be injected several times to reactivate the previously manufacture antibodies to continue protecting the body over the long term. A typical example of a vaccination schedule is the combined vaccine for diphtheria, tetanus and whooping cough. It’s given several times over our lives, with or without whooping cough. It can be given mixed, like its initial composition, or as a single vaccine based on the situation.

To continue reading, go to Vaccinating Women, Women who Become Pregnant and Breastfeeding Women.