Glossary

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antibody (AN-tih-bah-dee) An antibody is a protein made by your cells in your immune system. Antibodies fight invading germs.
disease (dih-ZEEZ) A condition that causes harm to the health of a person, animal, or plant.
pneumonia (nuh-MOHN-yuh) Pneumonia is a disease that causes a person’s lungs to fill with fluid. A person with pneumonia often has a fever, cough, and difficulty breathing.
vaccine (vak-SEEN) A vaccine is a weakened or dead form of a disease that is swallowed or injected into a person. This causes their body to fight the germs, and gives them the antibodies to fight that disease’s germs if the body comes in contact with them again.
virus (VY-russ) A virus is a very tiny germ that causes diseases. A virus can only be seen with a special kind of microscope.
immune system (ih-MYOON SIS-tum) Your immune system is a collection of proteins, cells, tissues, and organs that work together to protect your body from germs and infections.
contagious (kun-TAY-juss) When something is contagious, it spreads easily from person to person.
coronaviruses (kah-ROHN-uh-VY-ruh-sez) A coronavirus can infect animals and humans. COVID-19 is caused by a coronavirus.
infect (in-FEKT) To infect is to cause disease by introducing a virus.
vaccines (vak-SEENZ) A vaccine is a weakened or dead form of a disease that is swallowed or injected into a person. This causes their body to fight the germs, and gives them the ability to fight that disease’s germs if the body comes in contact with them again.
ambulance (AM-byoo-lenss) An ambulance is a specialized vehicle that is used to carry sick or very injured people to the hospital.
essential (ih-SEN-chull) Something that is essential is very important. Some types of workers are essential.
paramedic (payr-uh-MED-ik) A paramedic is a specially trained person who helps sick or injured people before and while they are being taken to the hospital.
quarantine (KWOR-un-teen) To be in quarantine is to stay away from others to avoid spreading illness.
epidemic (ep-ih-DEM-ik) An epidemic is when an unusually large number of people in one geographic area catch a virus.
outbreak (OWT-brayk) An outbreak of a disease is when the number of people coming down with it starts to climb.
pandemic (pan-DEM-ik) A pandemic is an epidemic that has spread all over the world.
climate change (KLY-mut CHAYNJ) Climate change is the change in an area's normal climate conditions (such as rain and temperature) over a long period of time.
economy (ih-KON-uh-mee) A country's economy is the way it runs its businesses, trade, and finances.
Great Depression (GRAYT dih-PRESH-un) The Great Depression was a time in the 1930s when the economy was greatly troubled. Many people were out of work, hungry, and homeless.