 How do vaccines help your body prepare to fight off harmful diseases? First, let's start off by introducing a group of sickening germs called pathogens. Picture pathogens the same way as you would the villains in a comic book series. These villains include some viruses, bacteria, fungi, and protozoa. They are microorganisms with a diabolical plan they wish to achieve to take up residence in your body. If they succeed, they could develop into a disease or illness. They achieve their goal by attacking, invading, and replicating inside your body, damaging our healthy cells. In this video, we'll focus our attention on viruses and bacteria, how your body's immune system defends against these invaders, and how we can help train our immune system to prepare it to prevent future infections. All right. First, let's talk a little bit more about bacteria. Bacteria are unicellular organisms, meaning they have one cell and can be found surprisingly everywhere. Thankfully, not all bacteria cause disease. Some are actually really beneficial to your body, like those that live in your intestines and aid digestion. However, there are also dangerous ones that are responsible for diseases like strep throat, tuberculosis, food poisoning, syphilis, and so on. Viruses are smaller than both human cells and bacteria, but where they lack in size, they make up an overall mightiness. Undoubtedly sneaky, viruses come in various forms and pack a punch once inside your body. They were produced by taking control of living cells in your body and using your cell's machinery to produce thousands of identical copies at a mind-blowing rate. Viruses are responsible for causing infectious disease like the common cold, flu, measles, Ebola, Zika, and so on. Sometimes prevention is much better than treatment. If you prevent a disease, you don't get sick in the first place. And if you're not sick, you can't spread the disease to others. How can we do this? By boosting the power of our immune system. The immune system is complicated, however greatly appreciated. It consists of various components that communicate and interact with one another to complete a critical task, keeping us healthy and alive by protecting our bodies from dangerous pathogens. The immune system has three main functions. First, it detects unrecognizable or abnormal material like those pathogens, viruses, bacteria, etc. Second, it attempts to kill or destroy the pathogens. And third, it keeps a memory of the pathogen in case it tries to invade again. Our white blood cells, aka lymphocytes, are the heroic warriors that terminate deadly pathogens. Using their power, they battle the pathogens and produce antibodies that help them identify and eliminate foreign material. But sometimes it can take a long time for our immune system to finally clear our bodies of foreign invaders. Fortunately, we are able to shorten this time using vaccines that act as an immune system accelerator. Vaccines primarily consist of a weakened, killed, or fragmented piece of a pathogen, not whole, live pathogens capable of causing illness. Once inside your body, the vaccine triggers an immune response, training your body to recognize and fight off the specific pathogen. If your body were to encounter this pathogen again, your immune system will be prepared to attack and destroy it more quickly, preventing you from getting sick and importantly from passing the illness on to others.