Vaccines aren’t cures, but they have prevented major illnesses and are a star player in the current fight against H1N1, or swine flu, scientists at the Oklahoma Medical Research Foundation said.
"Vaccines are not medicine, in the strictest sense of the word,” said Dr. Judith James. "Vaccines are actually filled with a dead or weakened virus or bacteria, which prompt your body to make its own medicine.”
When the vaccine is injected or inhaled in a spray form, components of the viruses or bacteria, also called antigens, make their way into the body.
The immune system goes on high alert, dispatching white blood cells, called B cells, to identify the intruders and figure out how to defeat them.
The B cells devise plans for creating proteins called antibodies that will kill the virus or bacteria and check in with T-helper cells, which act as supervisors, making sure that the antibodies won’t harm the body. Once the plans are approved, the B cell starts pumping out antibodies, making a surplus that can be used if you come into contact with the virus or bacteria again.
So the protection the flu shot gives you results not from the vaccine itself but from your body’s natural disease-fighter, the immune system.
Still, some vaccines must be renewed each year as new strains emerge.
"The reason we get a new flu shot annually is because the strain of influenza that causes seasonal outbreaks is always changing,” James said.
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