organisms that are too small to be seen without using a microscope
microbe
a condition that disrupts processes in the body
disease
parasites that can reproduce only inside the cells of plants, animals and bacteria. Many diseases like common cold, influenza, chickenpox and cold sores are caused by these
viruses
small single-celled prokaryotes that sometimes grow in or on human tissue and cause disease
bacteria
often found on rotting materials in a forest; they cannot move and therefore live on other dead and decaying materials
fungi
a single-celled or multi-celled organism with a simple biological structure
protist
an organism that lives on or in another organism, it takes nourishment from its victim
parasite
occurs when an infectious disease spreads to many people in one particular geographic area, in excess of the number of cases that might usually be expected
epidemic
occurs when an infectious disease spreads to millions of people around the world
pandemic
conditions and practices that help to maintain health and prevent the spread of diseases
hygiene
agent that causes illness or disease
pathogen
the cells in which another organisms lives or feeds
host cell
a chemical that kills or inhibits growth of bacteria
antibiotic
any substance which is used to stimulate the production of antibodies, in turn providing immunity against one or a few diseases
vaccine
the process whereby a person is made resistant to a disease, typically by the administration of a vaccine
immunization
can spread among a population in various ways, such as transfer of body fluids or contaminated food or water
infectious disease
the spread of disease from one person to another by close contact
contagion
any organism that can transmit a disease from one animal or plant to another (e.g. ticks)
vector
a person who has one copy of a mutated (changed) disease-causing gene but has no symptoms or mild symptoms
carrier
any cell or organism that possesses a clearly defined nucleus (e.g. plants and animals)
eukaryote
individual microscopic organism with no nucleus (e.g. bacteria)
prokaryote
A measure of how fast a new disease/illness spreads in a population over a period of time
rate of infection