Immunization: How Vaccines Work82719
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ANH20241 06:01

MEDICAL ANIMATION TRANSCRIPT: Immunization is the process of becoming immune to or protected against disease, usually by receiving a vaccine. Vaccines stimulate your immune system to protect you from certain diseases so you wont get sick or get an infection. Normally, the organs and cells of your immune system defend your body from harmful germs, such as bacteria and viruses. Immune cells are constantly circulating through your body. They monitor certain substances on the surfaces of cells, called antigens. Healthy cells have different antigens than diseased body cells or foreign invaders in the body. Immune cells usually ignore the antigens on healthy cells. But, when immune cells come across antigens on germs, they destroy the germ. Afterward, the immune cell displays the germ's antigen on its surface. This activates other types of immune cells to help get rid of the infection. For example, some activated immune cells recognize the antigen on infected body cells and then destroy them. Other activated immune cells, called plasma cells, make molecules called antibodies. These antibodies travel through your body and lock on only to germs that have its specific antigen. This marks the germ for destruction. Then other immune cells attack the germs that have these antibodies. Once the infection is gone, some of the immune cells that were exposed to the antigen become memory immune cells. In the future, if the same type of germ infects your body again, memory immune cells will be ready to destroy it so you dont get sick. This is called natural immunity. In many cases it will last your whole lifetime. The problem with getting natural immunity from having the disease itself, is that some naturally-acquired infections can cause serious complications or may even be deadly. For example, polio can result in permanent paralysis, or death. Measles can cause swelling of the brain, resulting in permanent brain damage or death, especially in children under age five. And, whooping cough, also known as pertussis, can cause complications such as pneumonia, slowed or stopped breathing, and death, especially in babies under one year of age. While symptoms may not be severe in all people, its not possible to know who will be infected enough to become very ill or even die. Vaccines can protect you from getting these diseases and their harmful symptoms. Each vaccine contains a small amount of weakened or killed germs. Usually, you receive a vaccine as a shot. Inside your body, the germ particles in the vaccine teach your immune cells to attack these germs. This process doesnt make you sick, but it does cause your body to make memory cells and antibodies for those germs. As a result, if that germ infects your body later in life, your immune system is ready to fight the infection so that you dont get sick. The main types of vaccines include live attenuated vaccines, inactivated vaccines, toxoid vaccines, and subunit and conjugate vaccines. Live attenuated vaccines use a live, but weakened germs. They are most like a natural infections and provide a strong disease immunity. Examples are the measles, mumps, rubella, chicken pox, and flu nasal spray vaccines. Inactive vaccines use inactive or killed germs. You may need several doses, or booster shots, over time. Examples are the hepatitis A, flu, polio, and rabies vaccines. Toxoid vaccines protect against harmful substances made by germs called toxins. They use weakened versions of the toxins, called toxoids. You may need booster shots to maintain protection against diseases. Examples are the diphtheria and tetanus parts of the DTaP vaccine. Subunit and conjugate vaccines use only a specific part of a germ. They provide strong immunity to that key part of the germ. These vaccines may also require booster shots. Examples are the pertussis part of the DTaP vaccine and the hepatitis B vaccine. Its important to know that vaccine not only protect you, but your community as well. Many diseases that vaccines prevent spread from person to person. When only a few people in your community are vaccinated, the risk of a disease outbreak is high. But, if most people are vaccinated, its much less likely for a disease to spread. This is called community, or herd immunity. Herd immunity is especially important to protect people who cant be vaccinated. This includes people with weakened immune systems, serious allergies, or other health conditions. Vaccines protect you, your family, and your community from diseases that can be dangerous or even deadly. To find out more about vaccines, talk to your healthcare provider. more