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Germs are very small organisms, or living things, that can cause people to get sick. They can cause you to get a stomach ache or get an infection in a cut on your hand. They are so small that you can't see them unless you use a high-powered microscope.
Doctors can use microscopes to determine what type of germs are causing someone to be sick. This allows them to determine the best medicine to help the person get well. There are different kinds of germs, but two of the most common are bacteria (say BACK-TEER-EE-YA) and viruses(say VY-RUHS-IZ).
Bacteria are little creatures made of one cell. They live everywhere and get their food from the environment they live in. For instance, bad bacteria in your mouth like to eat the sugar that sticks to your teeth. They then produce toxins (say TOK-SINS) that cause bad breath, gum disease, and cavities. The best way to prevent these germs is to brush and floss your teeth daily and eat a diet low in sugar so this bacteria has nothing to feed on. The picture to the right shows bacteria magnified 400 times (click the picture to view a larger version of it). This picture shows salmonella bacteria cells, which live in raw meat and other foods and can cause people to get very sick.
Viruses can only survive by living in the cells of a living thing like a person, plant, or animal. They can spread through the body and make its host (the plant, animal, or person it is living in) very sick. The flu, cold sores, and chicken pox are all caused by viruses.
While it is common to believe that all germs are bad, most germs do not harm you at all and some are even good for you. In the stomach there are helpful germs that help you digest your food and produce vitamins that keep you healthy. There are germs on your skin that keep your skin healthy and help keep bad germs from getting in your body. Some germs are actually grown to be used as medicine to fight other germs. Penicillin is a common medicine that actually comes from a mold and kills many harmful types of bacteria.
Some scientists now believe that being exposed to some germs is good for you because it helps build up your immune system(say IM-YOON SIS-TEM), your body's defense system to fight off and protect you from the bad germs. If your immune system meets some of these bad germs in small quantities, it will recognize them as being bad and be faster at fighting them off if a larger number enter your body later. Still, it is important to protect yourself from harmful germs so that you don't get sick.
The best way to fight bad germs is to wash your hands often with soap and warm water. But you need to be a good hand washer to help protect yourself from bad germs. When you wash your hands, first wet them with warm water. Then apply soap and form a lather by rubbing your hands together. Do this for about 15-20 seconds, or about the time it takes to sing the ABCs. Make sure to scrub in between your fingers and underneath your nails, as bad germs like to hide in these places. Rinse your hands well with warm water, then dry them with a clean towel. You should wash your hands after playing outdoors or touching animals, before you eat, after you use the bathroom, and after coughing or sneezing.
Another good way to fight bad germs is to take care of yourself. Eat lots of healthy foods like fruits, vegetables, and whole grains. These foods are very good for you and help strengthen your immune system, giving you a better chance to fight off diseases that could otherwise make you sick. Getting exercise and plenty of sleep also helps support your immune system.
This worksheet about germs has six pictures - kids can circle the ones that show germs being prevented and cross out the ones that show germs being spread.
Bacteria- small, single cell organisms that live almost everywhere. Some are harmful, but most are harmless and even helpful.
Viruses- small disease-causing agent that lives inside the cells of larger organisms, such as plants, animals, and humans.
Immune System- your body's defense system to help you fight off diseases and harmful germs.