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Germ Types

Bacteria (back-teer-eh-uh)

Bacteria are single cell organisms that live inside and outside of our bodies.  Bacteria get their nutrients from their environment and can reproduce quickly. When inside the body, bacteria can cause infections like sore throats (tonsillitis or strep throat), ear infections, cavities, and pneumonia. Common bacterial infections can be successfully treated by taking doctor-prescribed antibiotics.

Not all bacteria are bad. Good bacteria even live inside us. Good bacteria live in the intestines and help us use the nutrients in the food we eat. Some bacteria help scientists produce medicine and vaccines. Learn more about good bacteria.


Fungi (fun-guy)

Fungi are multi-celled, plant-like organisms. Mold and mildew fall within the fungi category. Fungi are not like other plants because they cannot make their own food from soil, water, and air. They get their nutrients from other plants, animals, and people. Fungi can cause illnesses like athlete’s foot and ringworm.

Fungi, mold, and mildew like damp, warm places like shower curtains and bathroom rugs. Fungi can cause problems when they are inhaled or start living on skin. Mold spores can be triggers for asthma attacks and allergic reactions. Following a regular household cleaning and disinfecting schedule can reduce the likelihood of encountering any serious problems from fungi.


Protozoa (pro-toh-zoh-uh)

Protozoa are one-cell organisms, such as amoebas, that often spread through moisture or water. They cause a range of intestinal infections that lead to diarrhea, nausea, and belly pain. Protozoa are spread through the food you eat, water you drink, and sometimes through insects. For example, malaria is spread by mosquitoes.


Viruses (vy-rus-iz)

Viruses are simpler than bacteria in structure and, unlike bacteria, they cannot multiply unless they are inside a living thing (host) like a plant, animal, or person. Viruses rely on the living thing to grow and reproduce. When viruses get inside peoples’ bodies, they can spread quickly and can make people sick. Viruses cause diseases like chicken pox, measles, and the flu. Viruses are NOT curable or treatable by antibiotics; however, there are antivirals that are effective against a few viruses like influenza. Viruses can survive on surfaces like doorknobs, countertops, and cell phones for an extended period of time, up to 48 hours, so it is important to wash your hands with soap often and to disinfect surfaces in the home frequently.

Find out more about these germs and how to use them in your classroom.

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