As a pet owner, you know that your puppy or kitten needs a series of vaccines – just like children do – to protect them from nasty illnesses. But do you know how vaccines work? And, are booster shots really necessary?
The Body’s Defense Mechanism
When the immune system is exposed to an infectious agent like bacteria or viruses, it responds by creating and enacting a “battle plan” to fight the intruder. Antibodies and various immune cells are produced to help kill or disarm the agent. Other cellular participants of the immune system are stimulated to remember what the infectious agent looks like should it ever be encountered again. Signs of illness in the patient result from both the “damage” caused by the infectious agent as well as the immune response. However, the next time the immune system is exposed to the same infectious agent, it can more quickly and efficiently disarm the invader before it can cause significant injury.
Vaccines – A Safe Shortcut
Vaccines serve to prepare the immune system for infectious invasion without having to expose the body to the fully armed intruder. To achieve this, vaccines contain killed or weakened infectious agents or parts of infectious agents. The goal is to trigger enough of an immune response to stimulate recognition of the agent and the creation of a battle plan without causing signs of illness.
A number of methodologies are used in the laboratory to alter infectious agents to make them safe for injection. For some infectious agents, steps are taken to inhibit their ability to spread throughout the body. Other agents may actually be killed with radiation or the addition of a chemical. The dead agent can neither reproduce nor produce toxins which might damage the body and yet its presence in the body will still stimulate the desired immune response. For other vaccines, only a part of the infectious agent may be injected or just an agent that mimics the infectious agent in appearance without inducing disease.
For some diseases, a single vaccination or infectious exposure is enough to protect the body for a lifetime. However, for other infectious diseases periodic re-exposure to the agent is required to remind the immune system to stay prepared. Check with your family veterinarian to see what vaccinations your pet needs updated.