antibiotic A germ-killing substance, usually prescribed as a medicine (or sometimes as a feed additive to promote the growth of livestock). It does not work against viruses.
bacteria (singular: bacterium) Single-celled organisms. These dwell nearly everywhere on Earth, from the bottom of the sea to inside other living organisms (such as plants and animals). Bacteria are one of the three domains of life on Earth.
Candida A genus of yeasts that are ubiquitous across the globe. More than 20 species have been linked to disease in people and animals.
Centers for Disease Control and Prevention, or CDC An agency of the U.S. Department of Health and Human Services, CDC is charged with protecting public health and safety by working to control and prevent disease, injury and disabilities. It does this by investigating disease outbreaks, tracking exposures by Americans to infections and toxic chemicals, and regularly surveying diet and other habits among a representative cross-section of all Americans.
climate change Long-term, significant change in the climate of Earth. It can happen naturally or in response to human activities, including the burning of fossil fuels and clearing of forests.
development (in biology) The growth of an organism from conception through adulthood, often undergoing changes in chemistry, size and sometimes even shape. (in economics and social sciences) The conversion of land from its natural state into another so that it can be used for housing, agriculture, or resource development.
fungus (plural: fungi) One of a group of single- or multiple-celled organisms that reproduce via spores and feed on living or decaying organic matter. Examples include mold, yeasts and mushrooms.
germ Any one-celled microorganism, such as a bacterium or fungal species, or a virus particle. Some germs cause disease. Others can promote the health of more complex organisms, including birds and mammals. The health effects of most germs, however, remain unknown.
infection A disease that can spread from one organism to another. It’s usually caused by some type of germ.
infectious An adjective that describes a type of germ that can be transmitted to people, animals or other living things.
innovation (v. to innovate; adj. innovative) An adaptation or improvement to an existing idea, process or product that is new, clever, more effective or more practical.
microbe Short for microorganism. A living thing that is too small to see with the unaided eye, including bacteria, some fungi and many other organisms such as amoebas. Most consist of a single cell.
pneumonia A lung disease in which infection by a virus or bacterium causes inflammation and tissue damage. Sometimes the lungs fill with fluid or mucus. Symptoms include fever, chills, cough and trouble breathing.
policy A plan, stated guidelines or agreed-upon rules of action to apply in certain specific circumstances. For instance, a school could have a policy on when to permit snow days or how many excused absences it would allow a student in a given year.
resistance (as in drug resistance) The reduction in the effectiveness of a drug to cure a disease, usually a microbial infection. (as in disease resistance) The ability of an organism to fight off disease. (as in exercise) A type of rather sedentary exercise that relies on the contraction of muscles to build strength in localized tissues. (in physics) Something that keeps a physical material (such as a block of wood, flow of water or air) from moving freely, usually because it provides friction to impede its motion.
strain (in biology) Organisms that belong to the same species that share some small but definable characteristics. For example, biologists breed certain strains of mice that may have a particular susceptibility to disease. Certain bacteria or viruses may develop one or more mutations that turn them into a strain that is immune to the ordinarily lethal effect of one or more drugs.
tract A particular, well-defined area. It can be a patch of land, such as the area on which a house is located. Or it can be a bit of real estate in the body. For instance, important parts of an animal’s body will include its respiratory tract (lungs and airways), reproductive tract (gonads and hormone systems important to reproduction) and gastro-intestinal tract (the stomach and intestines — or organs responsible for moving food, digesting it, absorbing it and eliminating wastes).
wake An area of disturbed air or water left behind an object (such as a boat or animal) moving through it. Also used to describe anything left behind some moving object of concept.