Bacteria are tiny living things, so small that you cannot see them without a special microscope. They are found almost everywhere on Earth, with billions on and inside your body.
Meet the Tiny World of Bacteria
Bacteria are single-celled organisms. They are much smaller than other cells and are considered one of the oldest and simplest forms of life on Earth. Scientists group bacteria by their different shapes, which include spherical (like tiny balls), rod-shaped, and spiral-shaped forms.
These microscopic organisms live in a wide variety of places. They are found in the air, water, and soil, and can even survive in extreme conditions like hot springs or deep underground. They live on your skin, in your mouth, and within your digestive system.
Good Bacteria vs. Bad Bacteria
While some bacteria can make you sick, many types are beneficial and help your body stay healthy. These “good” bacteria live mainly in your gut and on your skin, forming what is called your microbiome. They help your body break down food and absorb nutrients, which is important for digestion. Good bacteria also help produce certain vitamins and can prevent harmful bacteria from growing. Foods like yogurt and kefir contain live, active cultures of good bacteria, which can add more helpful bacteria to your digestive system.
Harmful bacteria, often called pathogens, can cause illness when they enter your body. They can reproduce quickly and sometimes release poisons, or toxins, that make you feel unwell. These “bad” bacteria can cause various infections, such as strep throat, ear infections, food poisoning, and urinary tract infections. Symptoms of sickness from bad bacteria can include tummy aches, fever, or difficulty breathing, depending on the type of infection.
Keeping Yourself Healthy
Practicing good hygiene habits helps keep bad bacteria away and prevents the spread of germs. Washing your hands regularly with soap and water is one of the best ways to protect yourself from getting sick. You should wet your hands, apply soap, and scrub all surfaces for at least 20 seconds, which is about how long it takes to sing “Happy Birthday” twice. Afterward, rinse your hands thoroughly under running water and dry them with a clean towel.
It is important to wash your hands before eating or preparing food, after using the bathroom, after playing outside, and after coughing or sneezing. When you cough or sneeze, it is helpful to cover your mouth and nose with a tissue or cough into your elbow. This helps stop germs from spreading into the air or onto your hands. Not sharing food or drinks with others also helps prevent the spread of bacteria that can make people sick.