What actually IS an immunization?

How does it work? Which diseases are preventable with vaccines? Why do some vaccines need "booster shots" and others don't?

An immunization is usually some dead or weakened form of a virus that your immune system is able to easily defeat. Once it knows how to defeat it, it can kill off the full strength version of the disease if you ever come in contact with it.

Some vaccines are given all at once, and some take a series of several immunizations to be fully protected... Hepatitis has a vaccine, but it takes the form of several different shots over a period of time. Polio has a vaccine, as do many forms of influenza.. there is now a vaccine for HPV, the virus that causes warts.

A vaccine is a small shot of the actual disease it is designed to fight. It lets your body build up a database of that disease and produces antibodies for any future fight.

Booster shots basically just give your antibodies a 'workout' every 5 years or so.

a vaccine is a small amount of the desease itself. It is suppossed to be so little an amount that your body is able to build antibodies to defeat it. This way if yoiu get the desease you are already prepared to fight it and effectively be immune.

the booster shots are necessary because deseases mutate and develop new strains which in turn need new antibodies.

Immunization occurs when a small amount of the targeted disease is injected into a person which allows the body's own immune defense mechanism to attack the disease and establish a natural immunity. Booster shots are often required re-enforce and strengthen the immunity.

immunization is something given to boost your immune system against a particular illness. Vaccinines are created sometimes with live virus of the particular illness or dead virus cells, when given to a patient it makes the body react to fight this foreign invasion and build an immunity to it so if you are exposed, you won't catch it. Some vaccines only keep their strength for a limited period of time. Tetnus shots are only good for 10 yrs, animal vaccines are only good for so long as eventually the immunity wears off in the body and has to be reintroduced to build it back up to an effective level.Why this is so for one thing and not another could be that technology has not developed life long lasting vaccines for all those diseases or the disease itself is not of a type that a vaccine will keep immunity up to life long levels high enough to keep you protected. It also depends on the species wether human or animal as to how long a vaccine will remain effective. Diseases have a habit of mutating and becoming different in some way so that a vaccine has to be re administered periodically or because the vaccine itself has been modified to defend against the new mutated strain of illness. Look at all the different types of flu there are out here now. As the particular flu virus mutates to get along with the shot, the next year a different type of flu shot will need to be given.