What is a vaccine?

A vaccine is a treatment designed to stimulate your immune system before you're exposed to the virus and bacteria so when you do encounter it, your body is ready to spring into action before it can make you sick. While many vaccines provide lifelong immunity, some require regular boosters. Today, more than 300 approved vaccines provide protection against 30 diseases.

There are two main types of vaccine: prophylactic, which prevents disease, and therapeutic, which treats disease. Prophylactic vaccines are extremely safe, although some may have mild side effects. The most common side effects are redness, soreness and irritation at the injection site and fever.

People with compromised immune systems, moderate to severe illnesses and/or those who have had a previous reaction to a vaccine should consult with their healthcare professional before getting vaccinated.

Researchers are working on vaccines that treat malaria, cancer, autoimmune diseases and neurological conditions such as Alzheimer's disease and Parkinson's disease.
When germs invade your body, you get sick. A vaccine helps prepare your body to fight against the germs. Vaccines are also called immunizations.

The diseases that vaccines protect against can cause severe sickness, handicaps, and even death. In years past, some of these diseases were common. But because of vaccines, most are now rare. Still, if people don't get vaccines, the diseases can become common again.

Vaccines are very safe for most people. There is a very small risk of serious problems. The risk from getting the diseases is far greater than any risk from getting the vaccine.

It's good to know what vaccines you and your children should have, and when. Talk to your doctor. If you have missed any vaccines, it's not too late to catch up!

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.